Plates Sentence Examples
She quickly put the plates in the dishwasher and dumped the stale water from the frying pan.
Mrs. Watson quietly swept their dirty plates away.
She stood and began removing the plates from the table.
Reminding herself that the mirror promised she wasn't as exposed as much breast as it looked from above, she left the ruffle on her arms and began filling their plates.
After a silent grace, they began filling their plates.
The second method, which he calls the "Promptuarium Multiplicationis" on account of its being the most expeditious of all for the performance of multiplications, involves the use of a number of lamellae or little plates of metal disposed in a box.
Alondra and Felipa remained focused on their plates.
Pete frowned at Bordeaux, who was carefully stacking the plates.
Before he signed off, he added, "Keep your eyes peeled for a Pace Arrow Motor home with California plates."
I had barely taken a sip when I had a vision of a motor home I'd recently seen in Keene, with California plates!
AdvertisementSitting on a secluded site at the far side of the circle, on the outside, sat a mid-sized Pace Arrow motor home with California Plates!
A tiny red haired woman, under five feet, Dean guessed, emerged from the vehicle that bore Colorado license plates.
There were linen napkins, two china plates and champagne flutes on top.
Gerald got a couple of plates from the cabinet and two knives.
Lana stood to the side, watching Kelli prepare two plates.
AdvertisementAfter leaving the room, Hunter stopped by a green Ford with Pennsylvania license plates.
She completed the sandwiches and put them on plates.
Buttoning a long shirt over her clothes, she joined him in the kitchen, where he was scooping scrambled eggs into two plates.
She shrugged and turned to the cabinet, removing some paper plates.
In Norwood and Rogers's process a thin coating of tin is applied to the iron before it is dipped in the zinc, by putting the plates between layers of granulated tin in a wooden tank containing a dilute solution of stannous chloride, when tin is deposited on them by galvanic action.
AdvertisementThe application of photography to exact astronomy has created the necessity for new forms of apparatus to measure the relative positions of stellar and planetary images on photographic plates, and the relative positions of lines in photographic spectra.
It is practically impossible to work with the sensitive film in contact with the reseau-film, not only because dust particles and contact would injure the silver film, but also because the plate-glass used for the photographic plates is seldom a perfect plane.
The armature consists of a bony case, partly composed of solid buckler-like plates, and partly of movable transverse bands, the latter differing in number with the species, and giving to the body a considerable degree of flexibility.
The revolving part is made with two side frames of cast iron or steel plates, and to these the lifting gear is attached.
Morse and Gale, who assisted him, found, however, that the distance of the plates up and down the canal must be at least three or four times the width of the canal to obtain successful results.
AdvertisementIf the current is interrupted or alternating, and if a telephone receiver has its terminals connected to a separate metallic circuit joined by earth plates at two other places to the earth, not on the same equipotential surface of the first circuit, sounds will be heard in the telephone due to a current passing through it.
He proposed that one ship should be provided with the means of making an interrupted current in a circuit formed partly of an insulated metallic wire connected with the sea at both ends by plates, and partly of the unlimited ocean.
Canal system of flow lines of current through the sea, and these might be detected by any other ships furnished with two plates dipping into the sea at stem and stern, and connected by a wire having a telephone in its circuit, provided that the two plates were not placed on the same equipotential surface of the original current flow lines.
On the question of how far the effects are due to conduction between the earth plates, and how far to true electromagnetic induction, authorities differ, some being of opinion that the two effects are in operation together.
If we suppose the cable interrupted at any place, and both sides of the gap earthed by connexion to plates, then the same conditions will still hold.
The idea was that variations of the primary current would create electromotive force in the secondary circuit which would act through the air condenser formed by the two plates.
He constructed one form of his coherer of a glass tube a few inches long filled with iron borings or brass filings, having contact plates or pins at the end.
In later improvements the secondary circuit of this jigger was interrupted by a small condenser, and the terminals of the relay and local cell were connected to the plates of this condenser, whilst the sensitive tube was attached to the outer ends of the secondary circuit.
His proposed radiator and absorber consisted of two wing-shaped plates of copper, the transmitter plates being interrupted in the centre by a spark gap, and the receiver plates by an inductance coil from the ends of which connexions were made to a coherer.
This alteration of charge caused a corresponding change in the mutual attraction of the plates of the condenser; hence the flexible plate was made to copy the vibrations of the diaphragm of the transmitter.
Some of the so-called " Orphic tablets," metrical inscriptions engraved on small plates of gold, chiefly dating from the 4th and 3rd centuries B.C., have been discovered in tombs in southern Italy, Crete and Rome.
The latter are plates of green tissue one cell thick, while the stem consists of uniform more or less elongated cylindrical cells.
The leaves of most mosses are flat plates, each consisting of a single layer of square or oblong assimilating (chlorophyllous) cells.
The sieve-tubes of the secondary phloem usually have very oblique end-walls bearing a row of sieve-plates; plates also occur on the radial side-walls.
In the red variety of Cucurbita pepo these crystals may consist of rods, thin plates, flat ribbons or spirals.
Sieve Tubes.The sieve tubes consist of partially fused rows of cells, the transverse cr lateral walls being perforated by minute openings, through which the contents of the cells are connected with each other, and which after a certain time become closed by,the formation of callus on the sieve plates.
Although for a time it was lost sight of on the continent, Sir Isaac Newton thought so highly of this book that he prepared an annotated edition which was published in Cambridge in 1672, with the addition of the plates which had been planned by Varenius, but not produced by the original publishers.
Dromaeognathae have a struthious palate, with a broad vomer meeting in front the broad maxillo-palatal plates, while behind it reaches the pterygoids.
The maxillopalatine plates (mxp) are dotted to show their spongy character.
The eye-end of the tube is closed by a metal plate having a small hole at its centre near the intersection of the glass plates.
He engraved about fifty plates, according to the usual reckoning; some thirty of them are mostly accounted indisputable - often large, full of figures, and highly studied.
It sublimes in thin plates of a dark colour and metallic lustre, and is soluble in solutions of the caustic alkalis.
In Ciampinus, Vetera Monumenta (Rome, 1747), plates xii., xiii., are several illustrations of actual examples.
In 1767 the Colebrookdale Iron Works cast a batch of iron rails or plates, each 3 ft.
Such metal plates, or " tie-plates," have come into considerable use also in the United States, where they are always made of rolled steel, punched with rectangular holes through which the spikes pass.
Later followed the appearance of lights; quasi-human voices; musical sounds, produced, it is said, without instruments; the "materialization" or presence in material form of what seemed to be human hands and faces, and ultimately of complete figures, alleged to be not those of any person present, and sometimes claimed by witnesses as deceased relatives; "psychography," or "direct writing and drawing," asserted to be done without human intervention; "spirit-photography," or the appearance on photographic plates of human and other forms when no counterpart was visible before the camera to any but specially endowed seers; 3 unfastening of cords and bonds; elongation of the medium's body; handling of red-hot coals; and the apparent passage of solids through solids without disintegration.
Here was what seems to have been the basement of a very large hall or " Megaron," approached directly from the central court, and near this were found further reliefs, fresco representations of scenes of the bull-ring with female as well as male toreadors, and remains of a magnificent gaming-board of gold-plated ivory with intarsia work of crystal plaques set on silver plates and blue enamel (cyanus).
The shapes of these ferruginous sandstones are very fantastic - tubes, hollow spheres, plates, &c., being common.
Through the commission the, money previously spent upon Queen's Plates is offered in the form of " King's Premiums " (to the number of twenty-eight in 1907) of L1 so each for thoroughbred stallions, on condition that each stallion winning a premium shall serve not less than fifty half-bred mares, if required.
Stomach generally provided with chitinous or calcified masticatory plates.
Cephalic shield short, truncated posteriorly; eyes deeply embedded; three calcareous stomachal plates; shell external, with reduced spire.
Margins of foot well developed; eyes superficial; three chitinous stomachal plates; shell external, with reduced spire.
Cephalic shield continuous with neck; twelve to fourteen stomachal plates; a posterior pallial filament passing through a notch in shell.
Cephalic shield ending posteriorly in a median point; shell internal, largely membranous; no radula or stomachal plates.
The platy minerals have also a perfect cleavage parallel to their flat surfaces, while the fibrous species often have two or more cleavages following their long axes; hence a schistose rock may split not only by separation of the mineral plates from one another but also by cleavage of the parallel minerals through their substance.
The head is usually connected with the thorax by a distinct membranous neck, strengthened in the more generalized orders with small chitinous plates (cervical sclerites).
Paired erectile plates (patagia) are borne on the prothorax in moths, while in moths, sawflies, wasps, bees and other insects there are small plates (tegulae) - see Fig.
The chief merit of the latter work lies in its forty plates, whereon the heads and feet of many birds are indifferently figured .2 But, while the successive editions of Linnaeus's great work were revolutionizing natural history, and his example of precision in language producing excellent effect on scientific writers, several other authors were advancing the study of ornithology in a very different way - a way that pleased the eye even more than his labours were pleasing the mind.
Far better both as draughtsman and as authority was George Edwards, who in 1 743 began, under the same title as Albin, a series of plates with letterpress, which was continued by the name of Gleanings in Natural History, and finished in 1760, when it had reached seven parts, forming four quarto volumes, the figures of which are nearly always quoted with approval.4 The year which saw the works of Edwards completed was still further distinguished by the appearance in France, where little had been done since Belon's days,' in six quarto volumes, of the Ornithologie of MathurinJacques Brisson - a work of very great merit so far as it goes, for as a descriptive ornithologist the author stands even now unsurpassed; but it must be said that his knowledge, according to internal evidence, was confined to books and to the external parts of birds' skins.
The success of Edwards's very respectable work seems to have provoked competition, and in 1765, at the instigation of Buffon, the younger d'Aubenton began the publication known as the Planches enlumineez d'histoire naturelle, which appearing in forty-two parts was not completed till 1780, when the plates' it contained reached the number of 1008 - all coloured, as its title intimates, and nearly all representing birds.
Latham entered, so far as the limits of his work would allow, into the 1 They were drawn and engraved by Martinet, who himself began in 1787 a Histoire des oiseaux with small coloured plates which have some merit, but the text is worthless.
In 1814 a sequel, The Zoological Miscellany, was begun by Leach, Nodder continuing to do the plates.
This was completed in 1817, and forms three volumes with 149 plates, 27 of which represent birds.
Frisch began the long series of works on the birds of Germany with which the literature of ornithology is enriched, by his Vorstellung der Vogel Teutschlands, which was only completed in 1763, and, its coloured plates proving very attractive, was again issued at Berlin in 1817.
Hayes's Natural History of British Birds, a folio with forty plates, appeared between 1771 and 1775, but was of no scientific value.
This is devoted to the very distinct and not nearly-allied groups of hornbills and of birds which for want of a better name we must call " Chatterers," and is illustrated, like those works of which a notice immediately follows, by coloured plates, done in what was then considered to be the highest style of art and by the best draughtsmen procurable.
The plates in this last are by Barraband, for many years regarded as the perfection of ornithological artists, and indeed the figures, when they happen to have been drawn from the life, are not bad; but his skill was quite unable to vivify the preserved specimens contained in museums, and when he had only these as subjects he simply copied the distortions of the " bird-stuffier."
A similar series of works was projected and begun about the same time as that of Le Vaillant by Audebert and Vieillot, though the former, who was by profession a painter and illustrated the work, was already dead more than a year before the appearance of the two volumes, bearing date 2802, and entitled Oiseaux dores ou a reflets metalliques, the effect of the plates in which he sought to heighten by the lavish use of gilding.
Temminck, whose father's aid to Le Vaillant has already been noticed, brought out at Paris a Histoire naturelle des pigeons illustrated by Madame Knip, who had drawn the plates for Desmarest's volume.3 Since we have begun by considering these large illustrated works in which the text is made subservient to the coloured plates, it may be convenient to continue our notice of such others of similar character as it may be expedient to mention here, though thereby we shall be led somewhat far afield.
Earliest in date as it is greatest in bulk stands Audubon's Birds of America in four volumes, containing four hundred and thirty-five plates, of which the first part appeared in London in 1827 and the last in 1838.
It does not seem to have been the author's original intention to publish any letterpress to this enormous work, but to let the plates tell their own story, though finally, with the assistance, as is now known, of William Macgillivray, a text, on the whole more than respectable, was produced in five large Ma egil- octavos under the title of Ornithological Biography, of liyr ay.
In 1830 John Edward Gray commenced the Illustrations of Indian Zoology, a series of plates of vertebrated animals, G w but mostly of birds, from drawings, it is believed by dlcke..
In this the large plates were reduced by means of the camera lucida, the text was revised, and the whole systematically arranged.
A Monograph of the Odontophorinae or Partridges of America (1850); The Birds of Asia, in seven volumes, the last completed by Mr Sharpe (1850-1883); The Birds of Great Britain, in five volumes (1863-1873); and The Birds of New Guinea, begun in 1875, and, after the author's death in 1881, undertaken by Mr Sharpe, make up the wonderful tale consisting of more than forty folio volumes, and containing more than three thousand coloured plates.
Moreover, both in drawing and in colouring there is frequently much that is untrue to nature, so that it has not uncommonly happened for them to fail in the chief object of all zoological plates, that of affording sure means of recognizing specimens on comparison.
In estimating the letterpress, which was avowedly held to be of secondary importance to the plates, we must bear in mind that, to ensure the success of his works, it had to be written to suit a very peculiarly composed body of subscribers.
An ambitious attempt to produce in England a general series of coloured plates on a large scale was Louis Fraser's Zoologia Typica, .
There are six hundred plates, but the exact number of species figured (which has been computed at six hundred and sixty-one) is not so easily ascertained.
The plates, which show no improvement in execution on those of Martinet, are after drawings by Huet and Pretre, the former being perhaps the less bad draughtsman of the two, for he seems to have had an idea of what a bird when alive looks like, though he was not able to give his figures any vitality, while the latter simply delineated the stiff and dishevelled specimens from museum shelves.
The Galerie des oiseaux, a rival work, with plates by Oudart,' seems to have been begun immediately after the former.
His portion is illustrated by two hundred and ninety-nine coloured plates that, wretched as they are, have been continually reproduced in various text-books - a fact possibly due to their subjects having been judiciously selected.
Then they set about a Second Series, which, forming a single volume with fifty-three plates, was finished in 1843.
Of the thirty-six plates illustrating this volume, a small folio, twenty are devoted to Ornithology, and contain figures, which, it must be allowed, are not very successful, of several species rare at the time.
The claim to that succession was made in 1845 by Des Murs for his Iconographie ornithologique, which, containing seventy-two plates by Prevot and Oudart l (the latter of whom had marvellously improved in his drawings since he worked with Vieillot), was completed in 1849.
Notwithstanding its name it only contains eighty plates, but of them forty-two, all by Pretre and in his usual stiff style, represent birds.
Between 1831 and 1834 the same author brought out, in continuation of his Centurie, his Illustrations de zoologie with sixty plates, twenty of which represent birds.
It now behoves us to turn to general and particularly systematic works in which plates, if they exist at all, form but an accessory to the text.
However, to have conceived the idea of executing a work on so grand a scale as this - it forms three folio volumes, and contains one hundred and eighty-five coloured and one hundred and forty-eight uncoloured plates, with references to upwards of two thousand four hundred generic names - was in itself a mark of genius, and it was brought to a successful conclusion in 1849.
Buller's beautiful Birds of New Zealand (4to, 1872- New 1873), with coloured plates by Keulemans, since the publi.
Its one hundred and fourteen plates by Ford truthfully represent one hundred and twenty-two of the mounted specimens obtained by the author in his explorations into the interior.
The former of these has the entire text, but no plates; the latter reproduces the plates, but the text is in places much condensed, and excellent notes are added.
Moreover, Dr Cornay's, scheme was not given to the world with any of those adjuncts that not merely please the eye but are in many cases necessary, for, though on a subject which required for its proper comprehension a series of plates, it made even its final appearance unadorned by a single explanatory figure, and in a journal, respectable and wellknown indeed, but one not of the highest scientific rank.
C. Eyton, who for many years had been forming a collection of birds' skeletons, began the publication of a series of plates representing them.
It is composed of figures of Christ, angels, prophets and saints, in Byzantine enamel run into gold plates.
In 1701, New York, seeking another claim, obtained from the Iroquois a grant to the king of England of this territory which they claimed to have conquered but from which they had subsequently been expelled, and this grant was confirmed in 1726 and again in 1744 About 1730 English traders from Pennsylvania and Virginia began to visit the eastern and southern parts of the territory and the crisis approached as a French Canadian expedition under Celeron de Bienville took formal possession of the upper Ohio Valley by planting leaden plates at the mouths of the principal streams. This was in 1749 and in the same year George II.
The frames into which hard soaps are ladled for cooling and solidification consist of rectangular boxes made of iron plates and bound and clamped together in a way that allows the sides to be removed when required; wooden frames are used in the case of mottled soaps.
It may be more conveniently prepared by passing the vapour of sulphur over red hot charcoal, the unccndensed gases so produced being led into a tower containing plates over which a vegetable oil is allowed to flow in order to absorb any carbon bisulphide vapour, and then into a second tower containing lime, which absorbs any sulphuretted hydrogen.
Potassium ruthenium cyanide, K4Ru(CN) 6.3H 2 O, formed when potassium ruthenate is boiled with a solution of potassium cyanide, crystallizes in colourless plates which are soluble in water.
Those in the Rudimentum novitiarum published at Lubeck in 1475 are from woodcuts, while the maps in the first two editions of Ptolemy published in Italy in 1472 are from copper plates.
The objection that a copper plate shows signs of wear after a thousand impressions have been taken has been removed, since duplicate plates are readily produced by electrotyping, while transfers of copper engravings, on stone, zinc or aluminium, make it possible to turn out large editions in a printing-machine, which thus supersedes the slow-working hand-press.
Owing to the great weight of stones, their cost and their liability of being fractured in the press, zinc plates, and more recently aluminium plates, have largely taken the place of stone.
Zincographs are generally used for producing surface blocks or plates which may be printed in the same way as a wood-cut.
Photographic processes have been utilized not only in reducing maps to a smaller scale, but also for producing stones and plates from which they may be printed.
Of Gerhard Kremer (1512-1594) Hondius has already been referred to as the purchaser of Mercator's plates.
He was distinguished as the discoverer of radioactivity, having found in 1896 that uranium at ordinary temperatures emits an invisible radiation which in many respects resembles Rntgen rays, and can affect a photographic plate after passing through thin plates of metal.
A third method consists in placing the specimen within bibulous paper, and enclosing the whole between two plates of coarsely perforated zinc supported in a wooden frame.
The zinc plates are then drawn close together by means of straps, and suspended before a fire until the drying is effected.
This was republished in a Latin translation with considerable alterations and omissions by Paolo Aringhi in 1651; and a century after its first appearance the plates were reproduced by Giovanni Bottari in 1737, and illustrated with great care and learning.
The middle valley is often intersected by vertical "crista" and "crochet" plates projecting into it from the anterior surface of the posterior transverse ridge or from the wall, the development of which is a useful guide in discriminating species, especially those known only by teeth and bones.
Gelatin forms a white amorphous powder; the commercial product, however, generally forms glassy plates.
As an example we may take the case of a solution of a salt such as copper sulphate in water, through which an electric current is passed between copper plates.
Volta's cell consists essentially of two plates of different metals, such as zinc and copper, connected by an electrolyte such as a solution of salt or acid.
The electromotive force of Volta's simple cell falls off rapidly when the cell is used, and this phenomenon was shown to be due to the accumulation at the metal plates of the products of chemical changes in the cell itself.
When the zinc and copper plates are connected through a wire, a current flows, the conventionally positive electricity passing from copper to zinc in the wire and from zinc to copper in the cell.
Plates of platinum and pure or amalgamated zinc are separated by a porous pot, and each surrounded by some of the same solution of a salt of a metal more oxidizable than zinc, such as potassium.
In ordinary cells the difference is secured by using two dissimilar metals, but an electromotive force exists if two plates of the same metal are placed in solutions of different substances, or of the same substance at different concentrations.
If we take as an example a concentration cell in which silver plates are placed in solutions of silver nitrate, one of which is ten times as strong as the other, this equation gives E = o 060 X Io 8 C.G.S.
Now let us disconnect the platinum plates from the battery and join them directly with the galvanometer.
A current will flow for a while in the reverse direction; the system of plates and acidulated water through which a current has been passed, acts as an accumulator, and will itself yield a current in return.
These phenomena are explained by the existence of a reverse electromotive force at the surface of the platinum plates.
The opposing force of polarization is about 1.7 volt, but, when the plates are disconnected and used as a source of current, the electromotive force they give is only about 1.07 volt.
This irreversibility is due to the work required to evolve bubbles of gas at the surface of bright platinum plates.
If the plates be covered with a deposit of platinum black, in which the gases are absorbed as fast as they are produced, the minimum decomposition point is 1.07 volt, and the process is reversible.
Marriott's Vestiarium Christianum (1868), though it must now be read with caution, is still of much value, notably the second part, which gives texts (with translations) of passages bearing on the subject taken from early and medieval writers, with many interesting plates.
Iron ships' plates have recently been coated with copper in sections (to prevent the adhesion of barnacles), by building up a temporary trough against the side of the ship, making the thoroughly cleansed plate act both as cathode and as one side of the trough.
Elmore, Dumoulin, Cowper-Coles and others have prepared copper cylinders and plates by depositing copper on rotating mandrels with special arrangements.
They all crystallize in the monoclinic system, often, however, in forms closely resembling those of the rhombohedral or orthorhombic systems. Crystals have usually the form of hexagonal or rhomb-shaped scales, plates or prisms, with plane FIG.
The ventral valve is usually the larger, and in many genera, such as Terebratula and Rhynchonella, has a prominent beak or umbo, with a circular or otherwise shaped foramen at or near its extremity, partly bounded by one or two plates, termed a deltidium.
Terebratula, that type of opening is found in the young stages only; later a it becomes partly closed by two plates which grow out from the sides of the delthyrium.
These plates are secreted by the ventral lobe of the mantle, and were named by von Buch in 1834 the " deltidium."
The two plates may meet in the middle line, and leave only a small oval opening near the centre for the pedicle, as in Rhynchonella; or they may meet only near the base of the delthyrium forming the lower boundary of the circular pedicle-opening, as in Terebratula; or the right plate may remain quite distinct from the left plate, as in Terebratella.
Both cotton and silk are woven, and plates, &c., are carved from soap-stone.
A little vinegar is poured into each pot; they are then covered with plates of sheet lead, buried in horse-dung or spent tanner's bark, and left to themselves for a considerable time.
After a month or so the plates are converted to a more or less considerable depth into crusts of white lead.
For the practical measurement of field intensity du Bois has used plates of the densest Jena flint glass.
If two iron plates, one of which is magnetized, are immersed in an electrolyte, a current will generally be indicated by a galvanometer connected with the plates.
The various comparisons previously made between the structure of Limulus and the Eurypterines on the one hand, and that of a typical Arachnid, such as Scorpio, on the other, had been vitiated by erroneous notions as to the origin of the nerves supplying the anterior appendages of Limulus (which were finally removed by Alphonse Milne-Edwards in his beautiful memoir (6) on the structure of that animal), and secondly by the erroneous identification of the double sternal plates of Limulus, called " chilaria," by Owen, with a pair of appendages (7).
The next four pairs of appendages (completing the mesosomatic series of six) consist, in both Scorpio and Limulus, of a base carrying each 130 to 150 blood-holding, leaf-like plates, lying on one another like the leaves of a book.
Their minute structure is closely similar in the two cases; the leaf-like plates receive blood from the great sternal sinus, and serve as respiratory organs.
Zoologists are familiar with many instances (fishes, crustaceans) in which the protective walls of a water-breathing organ or gill-apparatus become converted into an air-breathing organ or lung, but there is no other case known of the conversion of gill processes themselves into air-breathing plates.
There is no doubt that these are parapodial or limb appendages, carrying numerous imbricated secondary processes, and therefore comparable in essential structure to the leaf-bearing plates of the second meso somatic somite of Limulus.
It appears not improbable that the sternal plates wedged in between Fll '` vu...
That any partial fusion of originally distinct chitinous plates takes place in the cephalic shield of Trilobites, comparable to the partial fusion of bony pieces by suture in Vertebrata, is a suggestion contrary to fact.
It must always be remembered that we are liable (especially in the case of fossilized integuments) to attach an unwarranted interpretation to the mere discontinuity or continuity of the thickened plates of chitinous cuticle on the back of an Arthropod.
These plates may fuse, and yet the somites to which they belong may remain distinct, and each have its pair of appendages well developed.
On the other hand, an unusually large tergal plate, whether terminal or in the series, is not always due to fusion of the dorsal plates of once-separate somites, but is of ten a case of growth and enlargement of a single somite without formation of any trace of a new somite.
Opisthosoma confluent throughout its breadth with the prosoma, with the dorsal plate of which its anterior tergal plates are more or less fused; at most ten opisthosomatic somites traceable; the generative aperture thrust far forwards between the basal segments of the 6th appendages.
The salt separates from solutions containing hydrofluoric acid in large plates, which are greenish yellow in colour.
In his experiments upon this subject Fraunhofer employed plates of glass dusted over with lycopodium, or studded with small metallic disks of uniform size; and he found that the diameters of the rings were proportional to the length of the waves and inversely as the diameter of the disks.
The back of the obelisk is plain, but the front and sides are subdivided into storeys by a series of bands and plates, each storey having panels sunk into it which seem to represent windows with mullions and transom.
Both sexes wore many stamped gold plates sewn upon their clothes in lines or series.
They were supplied with simpler weapons and adornments, but even so their clothes had hundreds of stamped gold plates and strips of various shapes sewn on to them.
The iron plates, having been carefully cleaned with sand and hydrochloric or sulphuric acid, and lastly with water, are plunged into heated tallow to drive away the water without oxidation of the metal.
Heidenhain, on the other hand, rejected entirely the filtration view of lymph-formation, believing that the passage of lymph across the capillary wall is a true secretion brought about by the secretory function of the endothelial plates.
One of the bronze plates which decorated the exterior of the war-chest of the legio III.
Glass was largely used in pavements, and in thin plates as a coating for walls.
St Sofia when erected by Justinian had vaults covered with mosaics and immense windows filled with plates of glass fitted into pierced marble frames; some of the plates, 7 to 8 in.
The royal glass manufactory of La Granja de San Ildefonso was founded about 1725; in the first instance for the manufacture of mirror plates, but subsequently for the production of vases and table-ware in the French style.
Mirror plates previous to the invention had been made from blown " sheet " glass, and were consequently very limited in size.
De Nehou's process of rolling molten glass poured on an iron table rendered the manufacture of very large plates possible.
In regard to gold this has been proved to be so; gold leaf, or thin films of gold produced chemically on glass plates, transmit light with a green colour.
In the ruins of a building, attached by him to the temple of Nina, terra-cotta bas-reliefs of the king and his sons have been found, as well as the heads of lions in onyx, which remind us of Egyptian work and onyx plates.
This hopper was divided into two parts by vertical division plates, against the bottom edge of which the knives in the disk forced the roots and sliced and pulped them.
When this is done, the casing is hoisted out of the centrifugal and the vertical plates and the slabs of sugar are extracted.
In this form a large number, after being cooked or stoved in moist heat for about twenty-four hours, are piled between plates in an hydraulic press, and subjected to great pressure for a month or six weeks, during which time a slow fermentation takes place, and a considerable exudation of juice results from the severe pressure.
The former contains a mixture of semi-solid and molten metal, which is raked out into iron ladles and cast into plates of 66 to 77 lb weight, to be sold as "spelter."
At this period ploughs were made almost wholly of wood, the mouldboard being cased with plates of iron.
Cavies in general, the more typical representatives of the Caviidae, are rodents with hooflike nails, four front and three hind toes, imperfect collar-bones, and the cheek-teeth divided by folds of enamel into transverse plates.
They crystallize in plates, and for the most part distil without decomposition.
From his committee he reported in April 1888 the "Mills Bill," which provided for a reduction of the duties on sugar, earthenware, glassware, plate glass, woollen goods and other articles, the substitution of ad valorem for specific duties in many cases, and the placing of lumber (of certain kinds), hemp, wool, flax, borax, tin plates, salt and other articles on the free list.
It consists of a vertical column divided into a number of sections by horizontal plates, which are perforated so that the ascending vapours have to traverse a layer of liquid.
Really large meteors can be satisfactorily photographed, but small ones leave no impression on the plates.
The zoarium may rise up into erect growths composed of a single layer of zooids, the orifices of which are all on one surface, or of two layers of zooids placed back to back, with the orifices on both sides of the fronds or plates.
The body-wall is extensively calcified in the Cyclostomata and in most Cheilostomata, which may form elegant network-like colonies, as in the unilaminar genus Retepora, or may consist of wavy anastomosing plates, as in the bilaminar Lepralia foliacea of the British coasts, specimens of which may have a diameter of many inches.
The principle usually followed in the electrolytic refining of metals is to cast the impure metal into plates, which are exposed as anodes in a suitable solvent, commonly a salt of the metal under treatment.
It consists of a stoneware tank with a thin sheet of platinum-iridium alloy at either end forming the primary electrodes, and between them a number of glass plates reaching nearly to the bottom, each having a platinum gauze sheet on either side; the two sheets belonging to each plate are in metallic connexion, but insulated from all the others, and form intermediary or bi-polar electrodes.
Kellner has also patented a "bleaching-block," as he terms it, consisting of a frame carrying parallel plates similar in principle to those last described.
Yarnold's process, using corrugated glass plates coated on one side with gold or other metal leaf, is stated to have yielded as much as 2700 grains per e.h.p. hour.
The leading results were given in his Reisen durch verschiedene Provinzen des riissischen Reichs (3 vols., St Petersburg, 17 7 1-1776), richly illustrated with coloured plates.
A complete list of the plates and woodcuts (1731-1813) was published in 1814, and another list (1731-1818), in 1821.
The integuments of the head are divided into non-imbricate shields or plates, symmetrically arranged, but not corresponding in size or shape with the underlying cranial bones or having any relation to them.
The capacity of two parallel planes can be calculated at once if we neglect the distribution of the lines of force near the edges of the plates, and assume that the only field is the uniform field between the plates.
Let V 1 and V2 be the potentials of the plates, and let a charge Q be given to one of them.
In this calculation we neglect altogether the fact that electric force distributed on curved lines exists outside the interspace between the plates, and these lines in fact extend from the back of one "Edge plate to that of the other.
If all the plates on one side are connected together and also those on the other, the condensers are j oined i n parallel.
In the irregular crystalline aggregates branching and moss-like forms are most common, and in Transylvania thin plates or sheets with diagonal structures are found.
Copper plates amalgamated with mercury are also used when the gold is very fine, and in some instances amalgamated silver coins have been used for the same purpose.
In order to save finely divided gold, amalgamated copper plates are sometimes placed in a nearly level position, at a considerable distance from the head of the sluice, the gold which is retained in it being removed from time to time.
Similar plates are often used to catch any particles of gold that may be thrown back, while the main operation is so conducted that the bulk of the gold may be reduced to the state of amalgam by bringing the two metals into intimate contact under the stamp head, and remain in the battery.
In the process employed at the Worcester Works in the Transvaal, the liquors, containing about 150 grains of gold per ton and from 0.08 to o 01% of cyanide, are treated in rectangular vats in which is placed a series of iron and leaden plates at intervals of 1 in.
It is based upon the facts that concentrated hot sulphuric acid converts silver and copper into soluble sulphates without attacking the gold, the silver sulphate being subsequently reduced to the metallic state by copper plates with the formation of copper sulphate.
Since the action is sometimes very violent, especially when the bullion is treated in the granulated form (it is steadier when thin plates are operated upon), it is found expedient to add the acid in several portions.
The first dorsal fin and the ventrals are transformed into pointed formidable spines, and joined to firm bony plates of the endoskeleton.
The body is divided into eleven segments and the protrusible proboscis apparently into two, and the cuticle of the central segment is thickened to form three plates, one dorsal and two ventrolateral.
On the projecting plates supported by the handles are palmettes.
Besides these variations in the number of ridges or plates of which each tooth is composed, the thickness of the enamel varies so much as to have given rise to a distinction between a " thick-plated " and a " thin-plated " variety - the latter being most prevalent among specimens from the Arctic regions.
Tin amalgam is used for "silvering" mirrors, gold and silver amalgam in gilding and silvering, cadmium and copper amalgam in dentistry, and an amalgam of zinc and tin for the rubbers of electrical machines; the zinc plates of electric batteries are amalgamated in order to reduce polarization.
A pair of small plates - the tegulae - are very generally present at the bases of the fore-wings.
With the cheek-teeth formed of a number of parallel plates in the manner characteristic of the family, the viscacha is distinguished from the other members of that group by having only three hind toes; while it is also the heaviest-built and largest member of the group, with smaller ears than the rest.
In copying engraved plates for printing purposes, copper may be deposited upon the original plate, the surface of which is first rendered slightly dirty, by means of a weak solution of wax in turpentine or otherwise, to prevent adhesion.
Moulds for reproducing plates or art-work are often taken in plaster, beeswax mixed with Venice turpentine, fusible metal, or guttapercha, and the surface being rendered conductive by powdered black-lead, copper is deposited upon it evenly throughout.
Helmholtz in his " Ophthalmometer " has employed Clausen's principle, but arranges the plates so that both move symmetrically in opposite directions with respect to the telescope axis.
Many experiments have also been made by the use of photographic plates in order to find the greatest depth to which light penetrates.
Freezing takes place by the formation of pure ice in flat crystalline plates of the hexagonal system, which form in perpendicular planes and unite in bundles to form grains so that a thick covering of ice exhibits a fibrous structure.
During the rapid formation of ice the still unfrozen brine is often imprisoned between the little plates of frozen water; hence without some special treatment sea-ice is not suitable as a source of drinking water.
In steeply inclined seams passes or shoots leading to the main level below are sometimes used, and in Belgium iron plates are sometimes laid in the excavated ground to form a slide for the coal down to the loading place.
These consist essentially of links formed of a pair of parallel plates joined by a central bolt forming a scissors joint which is connected by chain links to the cage below and the winding-rope above.
When closed by the load the width is sufficient to allow it to enter a funnel-shaped guide on a cross-bar of the frame some distance above the bank level, but on reaching the narrower portion of the guide at the top the plates are forced apart which releases the ropes and brings the lugs into contact with the top of the cross-bar which secures the cage from falling.
The tubs are then removed or struck by the landers, who pull them forward on to the platform, which is covered with cast iron plates; at the same time empty ones are pushed in from the opposite side.
In his fifth year Tiglath-Pileser attacked Comana in Cappadocia, and placed a record of his victories engraved on copper plates in a fortress he built to secure his Cilician conquests.
Dean on the Great Western railway is made up of thirty flat plates, 7 ft.
The draw-bar is connected to the buckle, which is carried on rollers, the ends of the spring resting J on plates fixed to the under-frame.
It is a band of iron, enclosed in a circlet formed of six plates of gold, hinged one to the other, and richly jewelled and enamelled.
Shelley (4to, London, 1876-1880), in the coloured plates of which full justice is done to the varied beauties which these gloriously arrayed little beings display, while almost every available source of information has been consulted and the results embodied.
The north-west coast Indians hoisted the logs that formed the plates of their house frames into position with skids and parbuckles of rope.
In the Arctic and Pacific coast provinces, about Lake Superior, in Virginia and North Carolina, as well as in ruder parts of Mexico and South America, metals were cold-hammered into plates, weapons, rods and wire, ground and polished, fashioned into carved blocks of hard, tenacious stone by pressure or blow, overlaid, cold-welded and plated.
Phenosafranine is not very stable in the free state; its chloride forms green plates.
If the carbonate be in excess, the salt Na4Zr04 results, which when treated with water gives Na2Zr8017 12H20, which crystallizes in hexagonal plates.
The ash-pit is lined with iron plates to facilitate the recovery of metal accidentally spilt.
These, with other inscriptions on stone and on bronze plates brought home by Englishmen, found a cautious and sound interpreter in Osiander.
Now, it is evident that each coincidence of the perforations in the two plates is followed by a non-coincidence, during which the air-current is shut off, and that consequently, during each revolution of the upper plate, there occur n alternate passages and interceptions of the current.
In it the fixed and movable plates Do Siren.
Beneath the lower or fixed plate are four metallic rings furnished with holes corresponding to those in the plates, and which may be pushed round by projecting pins, so as to admit the air-current through any one or more of the series of perforations in the fixed plate.
But with larger plates, which alone will furnish the more complicated figures, a clamp-screw must be used for fixing the plate, and, at the same time, one or more other nodal points ought to be touched with the fingers while the bow is being applied.
Bells may be regarded as somewhat like circular plates vibrating with radial nodes, and with the edges turned down.
Among the wooden objects recovered from the relic beds were tubs, plates, ladles and spoons, a flail for threshing corn, a last for stretching shoes of hide, celt handles, clubs, long-bows of yew, floats and implements of fishing and a dug-out canoe 12 ft.
For domestic dishes they also made wooden tubs, plates, spoons, ladles and the like.
The anchors are built up of steel plates and angle bars, and are buried in a large mass of concrete.
The floor is of buckled plates paved with wood blocks.
Soft steel is used for rivets always, and sometimes for the whole superstructure of a bridge, but medium steel more generally for the plates, angle bars, &c., the weight of the bridge being then reduced by about 7% for a given factor of safety.
As to the maximum wind pressure on small plates normal to the wind, there is not much doubt.
The Edison electric meter, like those of Sprague and Lane-Fox, was based upon the principle that when an electric current flows through an electrolyte, such as sulphate of copper or sulphate of zinc, the electrodes being plates of copper or zinc, metal is dissolved off one plate (the anode) and deposited on the other plate (the cathode).
It consisted of a glass vessel, containing a solution of sulphate of zinc, in which were placed two plates of pure amalgamated zinc. These plates were connected by means of a german-silver shunt, their size and the distance between them being so adjusted that about ii 0 - 0 - part of the current passing through the meter travelled through the electrolytic cell and -j o i j of the current passed through the shunt.
Before being placed in the cells the zinc plates were weighed.
The shunted voltameter was then inserted in series with the electric supply mains leading to the house or building taking electric energy, and the current which passed dissolved the zinc from one plate and deposited it upon the other, so that after a certain interval of time had elapsed the altered weight of the plates enabled the quantity of electricity to be determined from the known fact that an electric current of one ampere, flowing for one hour, removes 1.2533 grammes of zinc from a solution of sulphate of zinc. Hence the quantity in amperehours passing through the electrolytic cell being known and the fraction of the whole quantity taken by the cell being known, the quantity supplied to the house was determined.
Owing to the cost and trouble of weighing a large number of zinc plates, this type of meter fell into disuse.
In the Long-Schattner electrolytic meter, the insertion of the coin depresses a copper plate or plates into an electrolytic cell containing a solution of sulphate of copper; the passage of the current dissolves the copper off one of the plates, the loss in weight being determined by the quantity of the electricity passed.
It is obtained as rhombic plates by mixing dilute solutions of calcium chloride and sodium phosphate, and passing carbon dioxide into the liquid.
The fluorine, which is liberated as a gas at the anode, is passed through a well cooled platinum vessel, in order to free it from any acid fumes that may be carried over, and finally through two platinum tubes containing sodium fluoride to remove the last traces of hydrofluoric acid; it is then collected in a platinum tube closed with fluor-spar plates.
Slates consist largely of thin plates of mica arranged parallel to the cleavage faces.
The splitter places a block on end between his knees, and with chisel and mallet splits it into as many plates as possible of the usual thickness for roofing purposes - namely, a quarter of an inch more or less according to the size and strength required.
These plates are then placed horizontally by the dresser on a vertical iron "stand," and cut with a sharp knife into slates of various sizes suitable for the market.
The last column in the Range Table giving the inches of penetration into wrought iron is calculated from the remaining velocity by an empirical formula, as explained in the article Armour Plates.
Further, unlike diamond, it never occurs as distinctly developed crystals, but only as imperfect six-sided plates and scales.
They consist of longitudinal columns, each composed of an immense number of "electric plates."
During his eleven years' ministry (1876-1878 with Depretis, 1884-1891 with Depretis and Crispi, 1896-1898 with Rudini), he succeeded in creating large private shipyards, engine works and metallurgical works for the production of armour, steel plates and guns.
The junction of the edges of the silver and copper-blend was treated with a flux of borax and the whole was submitted to the heat of a furnace until the silver was seen to be melting, when it was instantly removed, care being taken to avoid pressing upon the upper or lower surfaces, as the liquid silver in that case would have been squeezed out from between the two enclosing plates and the operation ruined.
A heavier value is shown by the precious metals -- the gold plates from Khorsabad (18) giving 129, and the gold daric coinage (21, 35) of Persia 129.2.
The silver plates at Khorsabad (18) we find to be 80 sigli of 84.6.
He has applied the theory with especial ingenuity to the interpretation of the circular bony plates in the carapace of the aberrant leather-back sea-turtles (Sphargidae) by prefacing an initial land phase, in which the typical armature of land tortoises was acquired, a first marine or pelagic phase, in which this armature was lost, a third littoral or seashore phase, in which a new polygonal armature was acquired, and a fourth resumed or secondary marine phase, in which this polygonal armature began to degenerate.
The Concord granite is a medium bluish-grey coloured muscovitebiotite granite, with mica plates so abundant as to effect the durability of the polish of the stone; it is used for building-the outer walls of the Library of Congress at Washington, D.C., are made of this stone-to a less degree for monuments, for which the output of one quarry is used exclusively, and for paving blocks.
One of his most important publications was La Geographie du moyen age (5 vols., Brussels, 1852-1857), with an atlas (1849) of fifty plates entirely engraved by himself, for he rightly attached such importance to the accuracy of his maps that he would not allow them to be executed by any one else.
In studying the dispersion of the aniline dyes, a prism with a very small refracting angle is made of two glass plates slightly inclined to each other and enclosing a very thin wedge of the dye, which is either melted between the plates, or is in the form of a solution retained in position by surface-tension.
This head-shield is succeeded by a varying number of free segments, each of which consists of a medium convex tergal piece and a pair of arched lateral plates, the pleura, of which there is one on each side.
This needle is suspended by a fine platinum silver wire, and its normal position is such that the aluminium paddle blades are just outside the quadrantal-shaped plates.
If the needle is connected to one terminal of a circuit, and the fixed plates or cells to the other member of the circuit, and a difference of potential is created between them, then the movable needle is drawn in so that the aluminium blades are more included between the fixed plates.
It was detected by Max Wolf at Heidelberg on plates exposed on Sept.
The salt crystallizes in large yellow plates, containing three molecules of water of crystallization.
The tubercles which cluster over the surface of the crown of the common pig are elongated and drawn out into the columns of the wart-hog, as the low transverse ridges of the mastodon's tooth become the leaf-like plates of the elephant's molar.
The Lamellibranchia are mainly characterized by the rudimentary condition of the head, and the retention of the primitive bilateral symmetry, the latter feature being accentuated by the lateral compression of the body and the development of the shell as two bilaterally symmetrical plates or valves covering each one side of the animal.
The chief points in which they vary are - (1) in the structure of the ctenidia or branchial plates; (2) in the presence of one or of two chief muscles, the fibres of which run across the animal's body from one valve of the shell to the other (adductors); (3) in the greater or less elaboration of the posterior portion of the mantle-skirt so as to form a pair of tubes, by one of which water is introduced into the sub-pallial chamber, whilst by the other it is expelled; (4) in the perfect or deficient symmetry of the two valves of the shell and the connected soft parts, as compared with one another; (5) in the development of the foot as a disk-like crawling organ (Arca, Nucula, Pectunculus, Trigonia, Lepton, Galeomma), as a simple plough-like or tongueshaped organ (Unionidae, &c.), as a re-curved saltatory organ (Cardium, &c.), as a long burrowing cylinder (Solenidae, &c.), or its partial (Mytilacea) or even complete abortion (Ostraeacea).
A further variation consists in the development of additional shelly plates upon the dorsal line between the two large valves (Pholadidae).
In Pholas dactylus we find a pair of umbonal plates, a dors-umbonal plate and a dorsal plate.
The filaments of the gill (ctenidium) of Mytilus and Arca thus form two closely set rows which depend from the axis of the gill like two parallel plates.
This is the condition seen in Arca and Mytilus, the so-called plates dividing upon the slightest touch into their constituent filaments, which are but loosely conjoined by their " ciliated junctions."
Section across the axis of a ctenidium with a pair of plates - flattened and shortened filaments - attached.
Modiolarcidae.-Foot with a plantar surface; the two branchial plates serve as incubatory pouches.
Shell with a pallial sinus; dorsal region protected by accessory plates.
The dentition is peculiar on account of the great size and complexity of the last upper molar, which is composed of about twelve plates, and exceeds in length the three teeth in front.
Each is an outgrowth of the body-wall at the side of the body, and consists of an axis containing two main vessels, an afferent and efferent, and bearing on either side a series of transverse plates whose blood-sinuses communicate with the vessels of the axis.
There are three pairs of rooted molars, whose crowns carry transverse plates, decreasing in number from three in the first to one in the last tooth.
The jugal is without an inferior angle, and extends forwards to the lachrymal; the palate is contracted in front and deeply emarginate behind; the incisors are short, and the molars divided by continuous folds into transverse plates; and the two halves of the lower jaw are welded together in front.
The Octodontidae, which are exclusively South American, differ from the preceding family by the tympanic bulla being filled with cellular bony tissue, and by the par-occipital process curving beneath it, while the cheek-teeth are almost or completely rootless and composed of parallel plates.
The species of Octodon have larger ears, longer, tufted tails and the sides of the cheekteeth indented by plates of enamel; they are chiefly found in hedgerows and bushes, where they burrow.
It is said that this was first spun in the island of Cos by Pamphile, daughter of Plates."
The interiors are gilt, often furnished with detachable plates and sometimes set with brilliants.
The hull of an iron or steel ship is a magnet, and the distribution of its magnetism depends upon the direction of the ship's head when building, this result being produced by induction from the earth's magnetism, developed and impressed by the hammering of the plates and frames during the process of building.
Another simple apparatus is a large vertical pipe or shoot in which sloping baffle plates or shelves are placed at intervals.
The architectural members of some of the treasure-houses have been found built into the Byzantine wall, or elsewhere on the site, as well as the terra-cotta plates that overlaid the stonework in some cases, and the pedimental figures, representing the battle of the gods and giants, from the treasure-house of the Megarians.
The "tangential arcs" (T) were explained by Young as being caused by the thin plates with their axes horizontal, refraction taking place through alternate faces.
An account of the order is given in Count Luigi Cibrario's Ordini Cavallereschi (Turin, 1846) with coloured plates of the costume and badges.
The best book of coloured plates is the Atlas der Alpenflora, in 5 vols., pub.
Let A and C be two fixed disks, and B a disk which can be brought at will within a very short distance of either A or C. Let us suppose all the plates to be equal, and let the capacities of A and C in presence of B be each equal to p, and the coefficient of induction between A and B, or C and B, be q.
Let us also suppose that the plates A and C are so distant from each other that there is no mutual influence, and that p' is the capacity of one of the disks when it stands alone.
The axis P N is made of varnished glass, and so are the axes that join the three plates with the brass axis N 0.
The axis N 0 passes through the brass piece M, which stands on an insulating pillar of glass, and supports the plates A and C. At one extremity of this axis is the ball D, and the other is connected with a rod of glass, N P, upon which is fixed the handle L, and also the piece G H, which is separately insulated.
The pins E, F rise out of the back of the fixed plates A and C, at unequal distances from the axis.
Following the nomenclature usual in connexion with dynamos we may speak of the conductors which carry the initial charges as the field plates, and of the moving conductors on which are induced the charges which are subsequently added to those on the field plates, as the carriers.
The wire which connects two armature plates for a moment is the neutralizing conductor.
The two curved metal plates constitute the field plates and must have original charges imparted to them of opposite sign.
The rotating balls are the carriers, and are connected together for a moment by a wire when in a position to be acted upon inductively by the field plates, thus acquiring charges of opposite sign.
In this way the charges on the field plates were continually replenished and reinforced.
Varley also constructed a multiple form of influence machine having six rotating disks, each having a number of carriers and rotating between field plates.
In this apparatus one of the charging rods communicated with one of the field plates, but the other with the neutralizing brush opposite to the other field plate.
Hence one of the field plates would always remain charged when a spark was taken at the transmitting terminals.
The studs on the armature plate were charged inductively by being connected for a moment by a neutralizing wire as they passed in front of the field plates, and then gave up their charges partly to renew the field charges and partly to collecting combs connected to discharge balls.
The glass plates are well varnished, and the carriers are placed on the outer sides of the two glass plates.
The moment, however, a pair of studs on the front plate are charged, they act as field plates to studs on the back plate which are passing at the moment, provided these last are connected by the back neutralizing wire.
P. Thompson's paper (loc. cit.), represents a view of the distribution of these charges on the front and back plates respectively.
Wimshurst constructed numerous very powerful machines of this type, some of them with "multiple plates, which operate i - almost any climate, and rarely fail to charge themselves and deliver a torrent of sparks between the disf El charge balls whenever the winch is turned.
Tudsbury that if an influence machine is enclosed in a metallic chamber containing compressed air, or better, carbon dioxide, the insulating properties of compressed gases enable a greatly improved effect to be obtained owing to the diminution of the leakage across the plates and from the supports.
The dorsal integument or mantle bears, not a simple shell, but eight calcareous plates in longitudinal series articulating with each other.
These projections are termed insertion plates; they are usually slit or notched to form teeth, the edges of which may be smooth and sharp, or may be crenulated.
Vermiform, with thick girdle and small valves; insertion and sutural plates strongly drawn forward, sharp and smooth.
No extra-pigmental eyes; insertion plates with pectinations between the fissures.
Later the ciliated ring or velum disappears and seven imbricated calcareous plates, made up of flattened spicules, are formed on the dorsal surface.
In the later Carboniferous rocks the earliest amphibians make their appearance in considerable numbers; they were all Stegocephalians (Labyrinthodonts) with long bodies, a head covered with bony plates and weak or undeveloped limbs.
The free pararosaniline, C19H19N30, and rosaniline, C20H21N30, may be obtained by precipitating solutions of their salts with a caustic alkali, colourless precipitates being obtained, which crystallize from hot water in the form of needles or plates.
Many fungi (Phallus, Agaricus, Fumago, &c.) when strongly growing put out ribbon-like or cylindrical cords, or sheet-like mycelial plates of numerous parallel hyphae, all growing together equally, and fusing by anastomoses, and in this way extend long distances in the soil, or over the surfaces of leaves, branches, &c. These mycelial strands may be white and tender, or the outer hyphae may be hard and black, and very often the resemblance of the subterranean forms to a root is so marked that they are termed rhizomorphs.
These reserve stores may be packed away in single hyphae or in swollen cells, but the hyphae containing them are often gathered into thick cords or mycelial strands (Phallus, mushroom, &c.), or flattened and anastomosing ribbons and plates, often containing several kinds of hyphae (Merulius lacrymans).
It forms orange-yellow plates and dyes wool a golden yellow (from an acid bath).
It is the last part of the metal to undergo this transformation and, when thus transformed, it is of constant though not atomic composition, and habitually consists of interstratified plates of its component metals.
The large massive plates of cementite which form the network or skeleton in hyper-eutectoid steels should, under distortion, naturally tend to cut, in the softer pearlite, chasms too serious to be healed by the inflowing of the plastic ferrite, though this ferrite flows around and Steel White Cast Iron 100 75 K 0 ?
Boiler plates undergo in sharing and assembling an intermediate degree of distort' and therefore they must be given an intermediate carbon-content, following the general rule that the carbon-content and hence the strength should be as great as is consistent with retaining the degree of ductility and the shock-resisting power which the object will need in actual use.
Thus the typical carbon-content may be taken as about o 05% for rivets and tubes, 0.20% for boiler plates, and 0.50 to 0.75% for rails, implying the presence of o 75% of cementite in the first two, 3% in the third and 7.5% to 11.25% in the last.
The impact face of these plates is given the intense hardness needed by being converted into high-carbon steel, and then hardened by sudden cooling.
The primary graphite (§ 26) generally forms a coarse, nearly continuous skeleton of curved black plates, like those shown in fig.
In strong contrast with this is the procedure in making rolled products such as rails and plates.
Great armour plates can indeed be made by rolling, because in making such flat plates the ingot is simply rolled back and forth between a pair of plain cylindrical rolls, like BB of fig.
Moreover, a single pair of rolls suffices for armour plates of any width or thickness, whereas if shafts of different diameters were to be rolled, a special final groove would be needed for each different diameter, and, as there is room for only a few large grooves in a single set of rolls, this would imply not only providing but installing a separate .set of rolls for almost every diameter of shaft.
C 6 H,N 2 Br 3, which crystallizes in yellow plates.
A very great feature of German and Russian work is the fur linings called rotondes, sacques or plates, which are made for their home use and exportation chiefly to Great Britain, America and France.
To the upper side of the parallel plates it is similar in construction to the theodolite.
The habits and dress of the various orders may be seen in Helyot's Histoire, which abounds in plates, coloured, in the ed.
There are plates representing members of the chief orders in Dugdale's Monasticon, and in the books of Gasquet and Steele mentioned above; also (coloured) in Tuker and Malleson, Handbook to Christian Rome, pt.
This condition can generally be satisfied with sufficient approximation with plates of reasonable dimensions.
It crystallizes in large colourless plates which possess a blue fluorescence.
Anthracite and steam-coal from the collieries of the coast and along the Loughor Valley are exported from the extensive docks; and there are also large works for the smelting of copper and the manufacture of tin plates.
It crystallizes in plates, and is soluble in water and alcohol.
Many states have been for a considerable time supplied by Krupp with steel guns and battleship plates.
Corn is threshed by a norag, a machine resembling a chair, which moves on small iron wheels or thin circular plates fixed to axle-trees, and is drawn in a circle by oxen.
The inference is that the "fatigue substances" generated in the muscle fibres in the course of their prolonged contraction injure and paralyse the motor end plates, which are places of synapsis between nerve cell and muscle cell, even earlier than they harm the contractility of the muscle fibres themselves.
The society of sciences, that of northern antiquaries, the natural history and the botanical societies, &c., publish their transactions and proceedings, but the Naturhistorisk Tidsskrift, of which 14 volumes with 259 plates were published (1861-1884), and which was in the foremost rank in its department, ceased with the death in 1884 of the editor, the distinguished zoologist, I.
Houses are keyed up with " shaps," " face plates " and " bolts," and only kept from falling by leaning on one another.
In Ulva and Mesocarpus the chromatophore is a single plate, which in the latter genus places its edge towards the incident light; in Spirogyra they are spiral bands embedded in the primordial utricle; in Zygnema they are a pair of stellate masses, the rays of which branch peripherally; in Oedogonium they are longitudinally-disposed anastomosing bands; in Desmids plates with irregular margins; in Cladophora polyhedral plates; in Vaucheria minute elliptical bodies occurring in immense numbers.
The wall consists of a basis of cellulose, and in some cases readily breaks up into a definite number of plates, fitting into one another like the plates of the carapace of a tortoise; it is, moreover, often finely sculptured or coarsely ridged and flanged.
Peysonellia squamaria, Melobesia lichenoides, Leathesia difformis are forms which are not attached throughout but grow in plates like the foliaceous lichens.
Seager's brilliant discoveries at Mokhlos were published (with coloured plates of the Early Minoan stone vases) in 1912.
The hydroxide is obtained as brown hexagonal plates by fusing thallic oxide with potash to which a little water has been added.
At the time of his death he was preparing an edition of his collected works, and the portions ready for the press were published in two volumes as Memoires de chimie in 1805 by his widow (in that year married to Count Rumford), who had drawn and engraved the plates in his Traite elementaire de chimie (1789).
George's Chapel, Windsor, are the stalls of the Knights of the Garter, in Henry VII.'s Chapel in Westminster Abbey are those of the Knights of the Bath, adorned with the stall plates emblazoned with the arms of the knight occupying the stall, above which is suspended his banner.
In the most primitive method thin plates of bronze were hammered over a wooden core, rudely cut into the required shape, the core serving the double purpose of giving shape to and strengthening the thin metal.
The Assyrians were perhaps the most remarkable of all ancient nations for the colossal size and splendour of their works in metal; whole circuit walls of great cities, such as Ecbatana, are said to have been covered with metal plates, gilt or silvered.
Of the two chief methods of working bronze, gold and silver, it is probable that the hammer process was first practised, at least for statues, among the Greeks, who themselves attributed the invention of the art of hollow casting to Theodorus and Rhoecus, both Samian sculptors, about the middle of the 6th century B.C. Pausanias specially mentions that one of the oldest statues he had ever seen was a large figure of Zeus in Sparta, made of hammered bronze plates riveted together.
Plates range in thickness from 4 in.
Armour plates which are several inches in thickness do not come in this group, being a special article of manufacture.
Short, sharp bends which are readily made in thin sheets cannot be done in thick plates, as the metal would be stressed too much in the outer layers.
The methods of union also differ, riveting being adopted for thick plates, and soldering or brazing generally for thin.
The divergence appears when plates are substituted for sheets.
Nearly all patterns are the developments of the envelopes of geometrical solids of regular or irregular outlines, few of plane faces; when they are made up of combinations of plane faces, or of faces curved in one plane only, there is no difference in dealing with thin sheets or thick plates.
In thick plates it is not attempted by hand, but pressing is done between dies, or segments of the sphere are prepared separately and riveted together.
In all work done in thick plates the dimensions marked out must have reference to the final shape of the article.
This is the case with gold, silver, copper, tin, lead and others, and especially with low carbon steel, which is first cast as an ingot, then annealed and rolled into plates as well as the thinnest sheets.
Steel intended for castings has slightly more carbon and other elements than the cast-steel ingot intended for rolling into plates.
It is continued until the contents of the pan have been coverted into a thick paste of small crystals of monohydrated sodium carbonate, permeated by a mother-liquor which is removed by draining on perforated plates or by a centrifugal machine, and is always returned to the pans.
It is very hard and but slightly malleable and flexible, although in thin plates it may be bent several times without breaking.
While most of the species are of interest chiefly to the conchologist, there are a number of edible forms. The shells of Placuna placenta, L., split into thin flat plates and, cut into small squares, are almost universally used in place of window glass.
If three plates (or three sets of exposures on one plate) are taken at intervals of six months, when the stars in the region have their maximum parallactic displacements, the first and third plates serve to eliminate the proper motion of the star, and the detection of a parallax is easy.
Their detection is especially simple when the stereo-comparator is used; this instrument enables the two eyes to combine the images of each star on two plates into one image (as in the stereoscope); when the star has moved considerably in the interval between the taking of the two plates, it appears to stand out from the rest in relief and is at once noticed.
It forms microscopic hexagonal plates having a silver-white streak.
The graves at Hallstatt were partly inhumation partly cremation; they contained swords, daggers, spears, javelins, axes, helmets, bosses and plates of shields and hauberks, brooches, various forms of jewelry, amber and glass beads, many of the objects being decorated with animals and geometrical designs.
The plates are placed in a vessel full of insulating oil which prevents the glow or brush discharge taking place over their edges.
All the tin foils on one side of the glass plates are connected together and all the tin foils on the opposite sides, so as to construct a condenser of any required capacity.
It has been found, however, that very efficient condensers can be made with compressed air as dielectric. If a number of metal plates separated by small distance pieces are enclosed in an iron box which is pumped full of air to a pressure, say, of 10o lb.
The people of India already possessed their Brahmi alphabet, of these alphabets is drawn from this work and from the same author's Indische Palciographie in the Grundriss der indo-arischen Philologie, to which is attached an atlas of plates (Strassburg, 1896), and in which a full bibliography is given.
The Museo Civico is housed in the Palazzo Malaspina and contains many interesting national relics and a small picture gallery, with a large collection of offprints on paper from niello plates, including a very fine "Fountain of Love" by Antonio Pollainolo; another fine old palace, the Palazzo Mezzabarba, is now used as the Municipio.
If the electrified body is touched against the upper plate whilst at the same time the lower plate is put to earth, the condenser formed of the two plates and the film of air or varnish becomes charged with positive electricity on the one plate and negative on the other.
On insulating the lower plate and raising the upper plate by the glass handle, the capacity of the condenser formed by the plates is vastly decreased, but since the charge on the lower plate including the gold leaves attached to it remains the same, as the capacity of the system is reduced the potential is raised and therefore the gold leaves diverge widely.
The most important applications of the theory of vibrations are to the case of continuous systems such as strings, bars, membranes, plates, columns of air, where the number of degrees of freedom is infinite.
A structure is composed, of pieces,such as the stones of a building in masonry, the beams of a timber frame-work, the bars, plates and bolts of an iron bridge.
It crystallizes in colourless plates and is readily soluble in alcohol, ether, &c., but not in water.
They agree with the true crabs in not having appendages (uropods) to the sixth segment of the pleon, the atrophy being complete in the Homolidae and Homolodromiidae, whereas in the Dromiidae and Dynomenidae a pair of small plates appear to be vestiges of these organs.
Tests made for several successive years by means of culture media and sterile plates, demonstrated the perfect bacteriologic purity of the air, first drawn into the caverns through myriads of rocky crevices that served as natural filters, then further cleansed by floating over the transparent springs and pools, and finally supplied to the inmates of the sanatorium.
The British Museum possesses a fine fibula of silver decorated with a simple pattern in niello and thin plates of repousse gold.
They are both of gold, and seem to be the covering plates of small pendant reliquaries about 1 in.
Vasari's account of this invention, given in his lives of Pollaiuolo and Maso Finiguerra, is very interesting, but he is wrong in asserting that Maso was the first worker in niello who took proofs or impressions of his plates.
It was then found that when the end plates of Volta's pile were connected to an electroscope the leaves diverged either with positive or negative electricity.
Volta maintained that the mere contact of metals was sufficient to produce the electrical difference of the end plates of the pile.
William Nicholson (1753-1815) and Sir Anthony Carlisle (1768-1840) in 1800 constructed a pile of silver and zinc plates, and placing the terminal wires in water noticed the evolution from these wires of bubbles of gas, which they proved to be oxygen and hydrogen.
In July 1808 Davy laid a request before the managers of the Royal Institution that they would set on foot a subscription for the purchase of a specially large voltaic battery; as a result he was provided with one of 2000 pairs of plates, and the first experiment performed with it was the production of the electric arc light between carbon poles.
Oersted's important discovery was the fact that when a wire joining the end plates of a voltaic pile is held near a pivoted magnet or compass needle, the latter is deflected and places itself more or less transversely to the wire, the direction depending upon whether the wire is above or below the needle, and on the manner in which the copper or zinc ends of the pile are connected to it.
He invented for this purpose a radiator consisting of two metal rods placed in one line, their inner ends being provided with poles nearly touching and their outer ends with metal plates.
Such an arrangement constitutes in effect a condenser, and when the two plates respectively are connected to the secondary terminals of an induction coil in operation, the plates are rapidly and alternately charged, and discharged across the spark gap with electrical oscillations (see Electrokinetics).
A pair of "post-branchial plates" projects backwards from the head.
This was successfully accomplished by the use of flexible paper matrices, from which metal plates could be cast in shaped moulds to any desired curve.
These plates were then fixed on the beds of the Hoe type revolving machine, which were adapted to receive them instead of the movable typeformes previously used.
The four cylinders, which are on the right-hand side of the press, are respectively the plates, four pages on each type cylinder, making a total of thirty-two pages in all.
Double sets of plates are placed on the main machine, which is capable of taking twenty-four pages, but by using narrower rolls the number of pages may be reduced to either sixteen or twenty if a smaller paper is desired.
Rosette " copper is obtained as thin plates of a characteristic dark-red colour, by pouring water upon the surface of the molten metal, and removing the crust formed.
They are square, oblong or circular in section, and the interior is fitted with horizontal or inclined plates or prisms, which regulate the fall of the ore.
In the Gerstenhoffer and Hasenclever-Helbig furnaces the fall is retarded by prisms and inclined plates.
In other furnaces the ore rests on a series of horizontal plates, and either remains on the same plate throughout the operation (0111vier and Perret furnace), or is passed from plate to plate by hand (Maletra), or by mechanical means (Spence and M`Dougall).
He cast crude copper, as obtained from the ore, into plates which were used as anodes, sheets of electro-deposited copper forming the cathodes.
The anodes are usually cast copper plates about (say) 3 ft.
Under the multiple system anodes and cathodes are placed alternately, all the anodes in one tank being connected to one rod, and all the cathodes to another, and the potential difference between the terminals of each tank is that between a single pair of plates.
Under the series system only the first anode and the last cathode are connected to the conductors; between these are suspended, isolated from one another, a number of intermediate bi-polar electrode plates of raw copper, each of these plates acting on one side as a cathode, receiving a deposit of copper, and on the other as an anode, passing into solution; the voltage between the terminals of the tank will be as many times as great as that between a single pair of plates as there are spaces between electrodes in the tank.
In time the original impure copper of the plates becomes replaced by refined copper, but if the plates are initially very impure and dissolve irregularly, it may happen that much residual scrap may have to be remelted, or that some of the metal may be twice refined, thus involving a waste of energy.
The attraction between the two plates was balanced by a weight put in the opposite pan.
Matters are so arranged by giving a torsion to the wire carrying the aluminium disk F that for a certain potential difference between the plates H and G, the movable part F comes into a definite sighted position, which is observed by means of a small lens.
Since the distribution of electricity may be considered to be constant over the surface S of the attracted disk, the mechanical force f on it is given by the expression,' f S(V - v)2 8 ird2 where d is the distance between the two plates.
If this distance is varied until the attracted disk comes into a definite sighted position as seen by observing the end of the index through the lens, then since the force f is constant, being due to the torque applied by the wire for a definite angle of twist, it follows that the difference of potential of the two plates varies as their distance.
If then two experiments are made, first with the upper plate connected to earth, and secondly, connected to the object being tested, we get an expression for the potential V of this conductor in the form V=A(d' - d), where d and d' are the distances of the fixed and movable plates from one another in the two cases, and A is some constant.
If W is the weight required to depress the attracted disk into the same sighted position when the plates are unelectrified and g is the acceleration of gravity, then the difference of potentials of the conductors tested is expressed by the formula V - V'=(d - d') /87 W where S denotes the area of the attracted disk.
In the dry pile electrometer a single gold-leaf is hung up between two plates which are connected to the opposite terminals of a dry pile so that a certain constant difference of potential exists between these plates.
If the gold-leaf is unelectrified, it is not acted upon by the two plates placed at equal distances on either side of it, but if its potential is raised or lowered it is attracted by one disk and repelled by the other, and the displacement becomes a measure of its potential.
In a similar manner, for systems used in photography, the vertex of the colour curve must be placed in the position of the maximum sensibility of the plates; G'; and to accomplish this the F and violet mercury lines are united.
His principal book, Historical and Statistical Information respecting the Indian Tribes of the United States, illustrated with 336 plates from original drawings, in part a compilation, was issued under the patronage of Congress in six quarto volumes, from 1851 to 1857.
According to a German tradition Schongauer was the inventor of printing from metal plates; he certainly was one of the first who brought the art to perfection.
In the upper chamber, about half-way between the centre of the base and the apex, was a single skeleton, adorned with beads, copper bracelets and plates of mica; in the lower chamber, directly under the upper and partly in the natural earth, were two skeletons, one adorned with beads and the other without ornament.
Thus a drop of train oil will spread itself over the surface of the sea till it shows the colours of thin plates.
When two parallel plates are placed vertically in a liquid the liquid rises between them.
Let l be the breadth of the plates measured perpendicularly to the plane of the paper, then the length of the line which bounds the wet and the dry parts of the plates inside is 1 for each surface, and on this the tension T acts at an angle a to the vertical.
If the distance between the inner surfaces of the plates is a, and if the mean height of the film of fluid which rises between them is h, the weight of fluid raised is pghla.
This expression is the same as that for the rise of a liquid in a tube, except that instead of r, the radius of the tube, we have a the distance of the plates.
We shall next consider the rise of a liquid between two plates of different materials for which the angles of contact are a l and a 2, the distance between the plates being a, a small quantity.
The force, therefore, with which the two plates are drawn together consists first of a positive part, or in other words an attraction, varying inversely as the square of the distance, and second, of a negative part of repulsion independent of the distance.
The fact that a pair of plates which repel one another at a certain distance may attract one another at a smaller distance was deduced by Laplace from theory, and verified by the observations of the abbe Haiiy.
If a small quantity of a liquid which wets glass be introduced between two glass plates slightly inclined to each other, it will run towards that part where the glass plates are nearest together.
If d is the distance between the plates at the edge of the film and II the atmospheric pressure, the pressure 2T of the liquid in the film is II - d cos a, and if A is the area of the film between the plates and B its circumference, the plates will be pressed together with a force 2AT cos a +BT sin a, and this, whether the atmosphere exerts any pressure or not.
By screening the various parts with metallic plates in connexion with earth, Beetz further proved that, contrary to the opinion of earlier observers, the seat of sensitiveness is not at the root of the jet where it leaves the orifice, but at the place of resolution into drops.
In the earlier stages of approximation the obstacle thus arising may not be important; but when the thickness of the layer of air is reduced to the point at which the colours of thin plates are visible, the approximation must be sensibly resisted by the viscosity of the air which still remains to be got rid of.
The total exports (foreign and coastwise) from Swansea during 1907 amounted to 4,825,898 tons, of which coal and coke made up 3, 6 55, 0 5 0 tons; patent fuel, 679,002 tons; tin, terne and black plates, 348,240 tons; liron and steel and their manufactures, 38,438 tons; various chemicals (mostly the by-products of the metal industries), 37,100 tons; copper, zinc and silver, 22,633 tons.
If then we prepare densely inseminated plates of these two bacteria in gelatine food-medium to which starch is added as the only carbohydrate, the bacteria grow but do not phosphoresce.
If we now streak these plates with an organism, e.g.
In this method the bacteria are distributed in a gelatine or agar medium liquefied by heat, and the medium is then poured out on sterile glass plates or in shallow glass dishes, and allowed to solidify.
To the bottom and muller are attached grinding plates (shoes and dies), which are replaced when worn; and to the sides three wings to deflect the moving pulp towards the centre, and thus establish the necessary pulp current.
Under his earlier patent of 1884, cast crude silver anode plates, about 4 in.
The alloy is cast into anode plates about s in.
Silver nitrate, AgNO 3, one of the most important silver salts, is obtained by dissolving the metal in moderately dilute nitric acid; on evaporation it separates in the anhydrous form as colourless triclinic plates.
His first communication to the Royal Society, read in June 1801, related to galvanic combinations formed with single metallic plates and fluids, and showed that an electric cell might be constructed with a single metal and two fluids, provided one of the fluids was capable of oxidizing one surface of the metal; previous piles had consisted of two different metals, or of one plate of metal and the other of charcoal, with an interposed fluid.
Such specimens as have descended to us show that the golden bulla of the middle ages was usually hollow, being formed of two thin plates of metal stamped with the designs of obverse and reverse, soldered together at the edges and padded with wax or plaster.
In the Cirripedia it forms a fleshy " mantle " strengthened by shelly plates or valves which may assume a very complex structure.
In a few Entomostraca (some Phyllopoda and Ostracoda) the chitinous lining of the fore-gut develops spines and hairs which help to triturate and strain the food, and among the Ostracods there is occasionally (Bairdia) a more elaborate armature of toothed plates moved by muscles.
These spaces make up the apparent body-cavity, the ta, Stomach of common crab, true body-cavity or coelom having Cancer pagurus, laid open, been, for the most part, obliter showing b, b, b, some of the ated by the great expansion of calcareous plates inserted in the blood-containing spaces.
Although a few living species have the antlers in the form of simple spikes in the adult male, in the great majority of species they are more or less branched; while in some, like the elk and fallow-deer, they expand into broad palmated plates, with tines, or snags, on one or both margins.
There are important foundries, rolling mills for copper, steel and brass plates, chemical works, saw-milling, shipbuilding, tobacco, cotton, sugar, soap and other manufactures.
Owen to the typical representative of a group of gigantic, armadillo-like, South American, extinct Edentata, characterized by having the carapace composed of a solid piece (formed by the union of a multitude of bony dermal plates) without any movable rings.
There are great iron and steel works, producing every kind of heavy goods used by railway and engineering works, such as boiler plates, rails, axles, tubes, bolts and nuts.
The bracing is accomplished by the introduction at the angles of the columns and girders or beams of gusset plates or knee braces, or by diagonal straps or rods properly attached by rivet or pin connexions.
Steel plates and shapes, when delivered from the rolls which form them to the cooling beds, are largely covered with scales, which, adhering only partially to the surface, offer the intervening cracks or joints as vulnerable points for rust.
Columns are generally built of riveted work of zedbars, channels, angles, plates, or lattice, of such form as will make the simplest and most easily constructed framing in the particular position in which the column is placed.
Sometimes the beams rest upon the girders, and are riveted through the flanges to it; in this case the abutting ends of beams are spliced by scarf plates placed on each side of the webs and secured by rivets.
All abutting joints in riveted work are faced to exact lengths and absolutely at right angles to the axis of the piece, and are spliced by scarf plates of proper dimensions adequately secured by rivets.
The secondary phloem contains numerous thick-walled fibres, parenchymatous cells, and large sieve-tubes with plates on the radial walls; swollen parenchymatous cells containing crystals are commonly met with in the cortex, pith and medullary-ray tissues.
An anatomical peculiarity in the veins of Pinus and several other genera is the continuity of the medullary rays, which extend as continuous plates from one end of the leaf to the other.
Sarre of Berlin and published in 1901 (Denkmi ler Persischer Baukunst; 65 large folio plates).
The paper, the printing, the plates, were all of the meanest description.
The infra-red requires special appliances; it has been examined visually by the help of phosphorescent plates (Becquerel), and with special photographic plates (Abney); but the most efficient way is to use the bolometer or radiomicrometer; by this means some 500 or 600 lines have been mapped.
On some plates the stars were allowed to trail and the planet was followed, in others the reverse procedure was taken; in either case the planet's position is measured by referring it to " comparison stars " of approximately its own magnitude situated within 25' to 30' of the centre of the plate, while these stars are themselves fixed by measurement from brighter " reference stars," the positions of which are found by meridian observations if absolute places are desired.
Hinks, and includes the material from some hundreds of plates taken at twelve observatories; in general it may be said the discussion proves that the material is distinctly heterogeneous, and that in places where it would hardly be expected.
The cheek-teeth have transverse plates of enamel on the crowns; the number of such plates diminishing from three in the first tooth to one or one and a half in the third.
In Emery's testing machine there are no knife-edges, but their function is performed by thin steel plates, which are forced under a very heavy pressure into slots formed in the parts that are to be connected, so that the parts are united by the plate.
But the resistance to bending of the steel plates would render this arrange - ment unsuitable for scale-beams, in which the movement is large.
These rods pass through holes in the front and back plates of the box, and are furnished with spiral springs, which (when the rods are forced back by hand) are in compression between the back plate of the box and shoulders on the rods.
The new Kessler furnace is a very ingenious apparatus, in which the fire from a gas-producer travels over the sulphuric acid contained in a trough made of Volvic lava, and surmounted by a number of perforated plates, over which fresh acid is constantly running down; the temperature is kept down by the production of a partial vacuum, which greatly promotes the volatilization of the water, whilst retarding that of the acid.
The walls of the calices and coenenchymal tubes are formed of flat plates of calcite, which are so disposed that the walls of one tube enter into the composition of the walls of adjacent tubes, and the walls of the calices are formed by the walls of adjacent coenenchymal tubes.
This skeleton is largely composed of a number of radiating plates or septa, and it differs both in origin and structure from the calcareous skeleton of all Alcyonaria except Heliopora.
The cells forming the limbs of the ectodermic folds secrete nodules of calcite, and these, fusing together, give rise to six (or twelve) vertical radial plates or septa.
In some corals the septa are solid imperforate plates of calcite, and their peripheral ends are either firmly welded together, or are united by interstitial pieces so as to form imperforate theca.
The pulley is in halves to facilitate fixing, and when in place the sections C are joined by plates E, bolted or riveted to the rim.
I have refracted it with Prismes, and reflected it with Bodies, which in Day-light were of other colours; I have intercepted it with the coloured film of Air interceding two compressed plates of glass, transmitted it through coloured Mediums, and through Mediums irradiated with other sorts of Rays, and diversly terminated it; and yet could never produce any new colour out of it.
He succeeded in explaining the colour of thin and of thick plates, and the inflexion of light, and he wrote on double refraction, polarization and binocular vision.
All these parts are supported by plates or ossicles of crystalline carbonate of lime.
The cup, in its simplest form, consists of two circlets of five plates.
Each plate of the upper circlet supports an arm, and is called a "radial"; the plates of the lower circlet, the "basals," rest on the stem and alternate with those of the upper circlet, i.e.
Some crinoids have yet another circlet below these, the constituent plates of which are called "infrabasals," and are situated radially.
Some of the thecal plates, infrabasals I B, basals B, and orals 0 are forming around the bodycavities r.pc and l.pc; p is the water-pore.
The theory was that all the plates just described, and more particularly those of the cup, which were termed "the calycinal system," could be traced, not merely in all crinoids, but in all Echinoderms, whether fixed forms such as cystids and blastoids, or free forms such as ophiuroids and echinoids, even - with the eye of faith - in holothurians.
MacBride (op. cit.), who has insisted that in the fixed stage of the developing starfish, Asterina, the relations of these plates to the stem are quite different from those which they bear in the developing and adult crinoid.
Those plates are perhaps constant throughout sea-urchins and starfish (though it would puzzle any one to detect them in certain Silurian echinoids), and they may be traced in some of the fixed echinoderms; but there is no proof that they represent the radials of a simple crinoid, and there are certainly many cystids in which no such plates existed.
Although, in the extreme correlation of the radial food-grooves, nerves, watervessels, and so forth, with a radiate symmetry of the theca, such a type differs from the Cystidea, while in the possession of jointed processes from the radial plates, bearing the grooves and the various body-systems outwards from the theca, it differs from all other Echinoderms, nevertheless ancient forms are known which, if they are not themselves the actual links, suggest how the crinoid type may have been evolved from some of the more regular cystids.
Beneath each food-groove was a radial water-vessel and probably a nerve and blood-vessel, all which structures passed either between certain regularly arranged thecal plates, or along a furrow floored by those plates, which were then in two alternating series.
The simpler forms of Edrioasteroidea, with their more sac-like body and undifferentiated plates, may well have been derived from early Cystidea of yet simpler structure, and there seems no reason to follow Jaekel in regarding the class as itself the more primitive.
The plates of the test are not drawn; their probable appearance may be gathered from fig.
These two types are, in the main, correlated with two gradual differentiations in the minute structure of the thecal plates.
Originally the calcareous substance of the plates (stereom) was pierced by irregular canals, more or less vertical, and containing strands of the soft tissue (stroma) that deposited the stereom, as well as spaces filled with fluid.
At last a quinqueradiate symmetry influenced the plates of the theca, partly through the development of a plate at the end of each groove (terminal), partly through plates at the aboral pole of the theca (basals and infrabasals) arising in response to mechanical pressure, but soon intimately connected with the cords of an aboral nervous system.
Before the latter plates arose, the stem had developed by the elongation and constriction of the fixed end of the theca, the gradual regularization of the plates involved, and their coalescence into rings.
These constituted the arms (brachia), and five definite radial plates of the theca were specialized for their support.
Chirocrinus-alter, one of of the nervous, waterthe Rhomb i fera, showing the reduced vascular and blood-vas number and regular arrangement of the cular systems, testified thecal plates, and the concentration of to their Pelmatozoan ancestry.
Such a form as this, when once its covering-plates had atrophied, would be a cone rcrq plates interam bullr /rctl plates hydropore frame A B FIG.
Spencer to have had in its ambulacra an inner as well as an outer series of plates.
In more typical echinoids the covering-plates alone remained to form the ordinary ambulacral plates, while the flooring-plates disappeared, the canals and other organs remaining as before.
The genital organs in both Asteroidea and Echinoidea would retain the interradial position they first assumed in Edrioaster; and in Echinoidea their primitive temporary openings to the exterior were converted into definite pores, correlated with five interradially placed plates at the aboral pole.
In the Echinoidea the water-canals and associated structures, ending in the terminal plates, stretched right up to these genital plates; but in the Asteroidea they never reached the aboral surface, so that the terminals have always been separated from the aboral pole by a number of plates.
These either are close to the mouth or are removed from it upon a series of ambulacral or subambulacral plates not derived immediately from thecal plates, or are separated from the oral centre by hypothecal passages passing beneath tegminal plates.
The stereom and stroma become arranged in folds and strands at right angles to the sutures of the thecal plates; in higher forms the stereom-folds are in part specialized as pectini-rhombs.
The Protocrinidae lead up to Proteroblastus, in which the theca is ovoid, sometimes prolonged into a stem, the plates differentiated into (a) smooth, irregular, depressed interambulacrals, (b) transversely elongate brachioliferous adambulacrals, to which the diplopores, which lie at right angles to the main food-groove, are confined.
Grooves and peristome protected by small plates, which can open over the grooves.
The generative organs arid coelom probably did not send extensions along the rays into the brachioles; but apparently nerves from the aboral centre, after passing through the thecal plates, met in a circumoral ring, from which branches passed into the plate under each main food-groove, and thence supplied the brachioles.
The thecal plates, however irregular in some species, always show defined basals and a distinct plate ("radial") at the end of each ambulacrum; they are in all cases so far affected by pentamerous symmetry that their sutures never cross the ambulacra.
Pelmatozoa in which epithecal extensions of the food-grooves, ambulacrals, superficial oral nervous system, blood-vascular and water-vascular systems, coelom and genital system are continued exothecally upon jointed outgrowths of the abactinal thecal plates (brachia), carrying with them extensions of the abactinal nerve-system.
Below these is always a circlet, or traces of a circlet, of plates alternating with the radials, i.e.
In some forms at least, pores between (not through) the ambulacral elements, or between them and the thecal plates, seem to have permitted the passage of extensions from the perradial water-vessels.
The calcareous skeleton, which may be entirely absent, is usually in the form of minute spicules, sometimes of small irregular plates with no trace of a calycinal or apical system; to these is added a ring of pieces radiately arranged round the oesophagus.