Mag., December 1906) as follows: It consists of two glass vessels like test tubes one inside the other, the space between the two being exhausted.
She has all these tubes and wires coming out of her.
tubes of the basal perisarc do not remain FIG.
He was sprouting tubes from every orifice - and then some.
They are propagated by cuttings, or from the leaves, which are cut off and pricked in welldrained pots of sandy soil, or by the scales from the underground tubes, which are rubbed off and sown like seeds, or by the seeds, which are very small.
in diameter, and the smallest 2 in., are wrapped in asbestos, felt and other non-conducting materials, and are placed in wooden tubes laid under ground like water and gas pipes.
The walls are pitted, and protoplasmic connections between the laticiferous tubes and neighboring parenchyma-cells have been seen.
The manner in which the circulation of hot water takes place in the tubes is as follows.
The cells not only fuse together in longitudinal and transverse rows, but put out transverse projections, which fuse with others of a similar nature, and thus form an anastomosing network of tubes which extends to all parts of the plant.
radioisotope sources or X-ray tubes.
These spiracles, according to Hinds, are remarkable honeycomb-like structures, and perforations to the tracheal tubes have not been demonstrated.
Tubes formed by the elongation of single cells are found in bast fibres, tracheides, and especially in laticiferous cells.
Dean remembered them from the dime stores of his youth, tightly rolled little balls of cotton in every color of the rainbow, all stuffed in long plastic tubes.
A characteristic feature of the fungal vegetative plantbody (mycelium) is its formation from independent coenocytic tubes or cell-threads.
of the thallus, whatever its external form, by branched, continuous or septate, coenocytic tubes (Siphoneae and Fungi), or by simple or branched cell-threads (Red and many Green Algae), in both cases growing mainly or entirely at the apex of each branch, is almost universal in.
This takes the form of long usually richly branched tubes which penetrate the other tissues of the plant mainly in a longitudinal direction.
of laticiferous tubes arises (Papaveraceae, Hevea, &c.).
When this stage is reached the invading tubes and their ramifications frequently disappear, leaving the cells full of the bacterioids, as they have been called.
The formation of the conducting tubes or secretory sacs which occur in all parts of the higher plants is due either to the elongation of single cells or to the fusion of cells together in rows by the absorption of the cell-walls separating them.
Incomplete fusion occurs in sieve tubes.
These tubes penetrate to all parts of the plant and occur in all parts of the root, stem and leaves.
The sieve tubes contain a thin lining layer of protoplasm on their walls, but no nuclei, and the cell sap contains albuminous substances which are coagulable by heat.
These protoplasmic strands are, except in the _______ case of sieve tubes, so delicate that special methods have to be employed _______ to make them visible.
3.) The middle ear communicates with the mouth by the Eustachian tubes, which pass between the basisphenoid and basioccipital bones, and unite upon the ventral side of the sphenoid, a little behind its articulation with the pterygoids, where they open into the mouth cavity by a short membranous duct.
The walls of these tertiary tubes send out, in all directions, canaliculi aeriferi which, ending in slight swellings, recall the mammalian aveoli.
They are very thin-walled membranes, very poor in blood-vessels, formed by the bulged-out pleural or peritoneal covering of the lungs, through the parabronchial tubes of which they are filled with air.
bearings; in each case are openings, closed by sliding tubes, for examination and lubrication.
The stomach is beset throughout its length with numerous small, finger-like caecal tubes.
The excretory (malpighian) tubes are few in number, either four or six.
There are four malpighian tubes, and all five tarsal segments are usually recognizable.
They may be distinguished from the Malacodermata by the presence of only five or six abdominal sterna, while six malpighian tubes are present in some of the families.
- This is an important tribe of beetles, including families with four malpighian tubes and only five or six abdominal sterna, while in the thorax there is a backwardly directed process of the prosternum that fits into a mesosternal cavity.
There are either four or six malpighian tubes.
There are four malpighian tubes.
- The families of beetles included by Kolbe in this group are distinguished by the possession of six malpighian tubes, and a great reduction in one or two of the tarsal segments, so that there seem to be only four or three segments in each foot; hence the names Tetramera and Trimera formerly applied to them.
There are six malpighian tubes.
A second engine, the West Point, also built at West Point Foundry for the South Carolina railroad, differed from the Best Friend in having a horizontal boiler with 6 or 8 tubes, though in other respects it was similar.
Bursting of boilers or tubes, &c., of engines 13.
enough to carry heavy lighted sparks through the tubes and chimney.
In English practice where a spark-arrester is put in it usually takes the form of a wire-netting dividing the smoke-box horizontally into two parts at a level just above the top row of tubes, or arranged to form a continuous connexion between the blast-pipe and the chimney.
The heavy sparks are projected from the tubes in straight lines and are caught by the louvres L, L, L, and by them deflected downwards to the bottom of the smoke-box, where they collect in a heap in the space D round a tube which is essentially an ejector.
In the older type the combustion chamber (of metal or glass) is sunk in the calorimeter proper, tubes being provided for the entrance and exit of the gaseous substances involved in the action.
These tubes are generally in the form of worms immersed in the water of the calorimeter.
The shapes of these ferruginous sandstones are very fantastic - tubes, hollow spheres, plates, &c., being common.
Goodrich), that among the Hirudinea the coelom, which is largely broken up into narrow tubes, may be confluent with the tubes of the vascular system.
Ray Lankester to the members of a series of tubes, proved in some cases to be excretory in nature, which exist typically to the number of a single pair in most of the segments of the Chaetopod body, and open each by a ciliated orifice into the coelom on the one hand, and by a pore on to the exterior of the body on the other.
There is no possibility that sperm and ova can escape by these tubes not in company with coelomic fluid.
Benham) the sperm ducts are hardly to be distinguished from nephridia; they are sinuous tubes with an intra-cellular duct.
Vascular system generally present forming a closed system of tubes.
Nephridia sometimes of the type of those of the Oligochaeta; in other cases short, wide tubes with a large funnel serving also entirely or in part as gonad ducts.
In Polynoe the nephridia are short tubes with a slightly folded funnel whose lumen is intercellular, and this intercellular lumen is characteristic of the Polychaetes as contrasted with leeches and Oligochaetes.
Nephridia in two series; large, anterior nephridia followed by small, short tubes in abdomen.
Nephridia generally paired, often very numerous in each segment, in the form of long, much-coiled tubes with intracellular lumen.
The nephridia in this group are invariably coiled tubes with an intracellular lumen and nearly invariably open into the coelom by a funnel.
It has been ascertained that the nephridia of Oligochaeta are preceded in the embryo by a pair of delicate and sinuous tubes, also found in the Hirudinea and Polychaeta, which are larval excretory organs.
The oviducts are always short trumpet-shaped tubes and are sometimes reduced (Enchytraeidae) to merely the external orifices.
The sperm ducts are usually longer than the oviducts; but in Limicolae both series of tubes opening by the funnel into one segment and on to the exterior in the following segment.
Coelom generally reduced to a system of tubes, sometimes communicating with vascular system; in Acanthobdella and Ozobranchus a series of metamerically arranged chambers as in Oligochaeta.
These regions of the coelom end at the ends of the body and communicate with each other by means of a branched system of coelomic sinuses, which are in places very fine tubes.
The network is partly formed out of pigmented cells which are excavated and join to form tubes, the socalled botryoidal tissue, not found among the Rhynchobdellidae at all.
A further fact must be considered in deciding this question, which is the discovery of ramifying coelomic tubes, approaching close to, but not entering, the epidermis in the Polychaete Arenicola.
These tubes are lined by flattened epithelium and often contain blood capillaries; they communicate with the coelom and are to be regarded as prolongation of it into the thickness of the body wall.
It consisted of a graduated circle inside which another could slide, carrying two small tubes diametrically opposite, the instrument being kept vertical by a plumb-line.
19) are intended to show certain important distinctions which obtain amongst the various " introverts," or intro-and e-versible tubes so frequently met with in animal bodies.
It is clear that, if we start from the condition of full eversion of the tube and watch the process of introversion, we shall find that the pleurecbolic variety is introverted by the apex of the tube sinking inwards; it may be called acrembolic, whilst conversely the acrecbolic tubes are pleurembolic. Further, it is obvious enough that the process either of introversion or of eversion of the tube may be arrested at any point, by the development of fibres connecting the wall of the introverted tube with the wall of the body, or with an axial structure such as the oesophagus; on the other hand, the range of movement of the tubular introvert may be unlimited or complete.
The possession of a variable number of excretory tubes (Malpighian tubes), which are developed as outgrowths of the hind-gut and pour their excretion into the intestine,is also a distinctive character of the Hexapoda.
In insects of active flight on of Air-Tubes e ra Portion the tubes swell out into numerous Magnified 2 2 times.
- Nitrogenous waste-matter is removed from the body by the Malpighian tubes which open into the food-canal, usually where the hind-gut joins the stomach.
These tubes vary in number from four to over a hundred in different orders of insects.
The cells which line them and also the cavities of the tubes contain urates, which are excreted from the blood in the surrounding bodycavity.
When the worn-out cells are broken down, the urates are carried dissolved in the blood to the Malpighian tubes for excretion.
13) in the female are paired, each ovary consisting of a variable number of tubes (one in the bristle-tail Campodea and fifteen hundred in a queen termite) in which the eggs are developed.
coe, Caecal tubes (below them the stomach).
k, Kidney tubes.
tubes, those of each testis opening into a vas deferens.
The pits leading from these lengthen into tubes, and undergo repeated branching as development proceeds.
This by successive divisions forms a group of four to eight cells, which subsequently pass through the blastoderm, and dividing into two groups become symmetrically arranged and surrounded by the rudiments of the ovarian tubes.
g, Germ-cells surrounded by rudiment-cells of ovarian tubes.
Brauer in his arrangement of these orders laid special stress on the nature of the metamorphosis, and was the first to draw attention to the number of Malpighian tubes as of importance in classification.
Numerous (30 or more) Malpighian tubes.
Malpighian tubes numerous (100-150).
Numerous (50-60) Malpighian tubes.
Six or eight Malpighian tubes.
Four Malpighian tubes.
Malpighian tubes numerous (40).
Malpighian tubes numerous (50-60).
Four or six Malpighian tubes.
Six Malpighian tubes.
Four (rarely 6 or 8) Malpighian tubes.
Numerous (20-150) Malpighian tubes (in rare cases, 6-12 only).
But the vestigial jaws, numerous Malpighian tubes, and specialized wings of may-flies forbid us to consider the order as on the whole primitive.
So the Dermaptera, which retain distinct maxillulae and have no ectodermal genital ducts, have either specialized or aborted wings and a large number of Malpighian tubes.
The Corrodentia retain vestigial maxillulae and two pairs of Malpighian tubes, but the wings are somewhat specialized in the Copeognatha and absent in the degraded and parasitic Mallophaga.
They differ from other Endopterygota in the multiplication of their Malpighian tubes, and from all other Hexapoda in the union of the first abdominal segment with the thorax.
The calyx is a long tube, or a series of connected tubes, situated above the core barrel, to which it is equal in diameter.
Nemertines live in the sea, some being common amongst the corals and algae, others hiding in the muddy or sandy bottom, and secreting gelatinous tubes which ensheath the body along its whole length.
First, he made a number of leathern tubes the ends of which he contrived to fix among the joists and flooring of a fine upper-room in which Zeno entertained his friends, and then subjected it to a miniature earthquake by sending steam through the tubes.
In large pans a mechanical stirring apparatus is provided, which in some cases, as in Morfit's steam " twirl," is formed of the steam-heating tubes geared to rotate.
As the animals become adult, diverticula arise on the tubes of these organs, which develop either spermatozoa or ova.
Also communicating with this pouch is a pair of long slender flagelliform tubes, of which the function is unknown.
Berthelot first accomplished the synthesis of benzene in 1870 by leading acetylene, HC: CH, through tubes heated to dull redness; at higher temperatures the action becomes reversible, the benzene yielding diphenyl, diphenylbenzene, and acetylene.
The oxidation with nitric acid in sealed tubes at a temperature of 150° to 200° for aliphatic compounds, and 250° to 260° for aromatic compounds, is in common use, for both the sulphur and phosphorus can be estimated, the former being oxidized to sulphuric acid and the latter to phosphoric acid.
There may be said to be three or four different modes of life in these larvae: some are fossorial, and form tubes in the mud or clay in which they live; others are found on or beneath stones; while others again swim and crawl freely among water plants.
epr, epiphysial tubes.
Tubes are generally made up around mandrels, and allowed throughout the curing to remain imbedded i n p u lverized French chalk, which affords a useful support for many articles that tend to lose their shape during the process.
Thence he was led to his famous researches on the phenomena produced by the discharge of electricity through highly exhausted tubes (sometimes known as "Crookes' tubes" in consequence), and to the development of his theory of "radiant matter" or matter in a "fourth state," which led up to the modern electronic theory.
While he also prevents interruption of the operation by means of water-jackets, he uses hot-blast, and produces, besides metallic lead, large volumes of lead fumes which are drawn off by fans through long cooling tubes, and then forced through suspended bags which filter off the dust, called "blue powder."
Suppose the whole space in which induction exists to be divided up into unit tubes, such that the surface integral of the induction over any cross-section of a tube is equal to unity, and along the axis of each tube let a line of induction be drawn.
Honda subjected tubes of iron, steel and nickel to the simultaneous action of circular and longitudinal fields, and observed the changes of length when one of the fields was varied while the other remained constant at different successive values from zero upwards.
Knott, who made an exhaustive series of experiments upon various metals in the form of tubes, concluded that in iron there was always a slight increase of volume, and in nickel and cobalt a slight decrease.
Both belong to the category of " coelomoducts," namely, r- ' tubular or funnel-like portions of the coelom opening to the exterior in pairs in each somite (potentially,) and usually persisting in only a few somites as either "urocoels" (renal organs) or "gonocoels"(genital tubes).
Scorpio is here provided with a single or double pair of renal excretory tubes, which have been identified by earlier authors with the Malpighian tubes of the Hexapod and Myriapod insects.
Limulus is devoid of any such tubes.
It is not a pair of simple tubes, nor of dendriform tubes, but a closed network.
Limulus agrees with the majority of the Crustacea in being destitute of renal excretory caeca or tubes opening into the hinder part of the gut.
(From Lankester, loc. cit., after Packard.) with all air-breathing Arthropoda except Peripatus, possesses these tubules, which are often called Malpighian tubes.
It has been considered by them as proving that Limulus, in spite of all its special agreements with Scorpio (which, however, have scarcely been appreciated by the writers in question), really belongs to the Crustacean line of descent, whilst Scorpio, by possessing Malpighian tubes, is declared to be unmistakably tied together with the other Arachnida to the tracheate Arthropods, the Hexapods, Diplopods, and Chilopods, which all possess Malpighian tubes.
It must be pointed out that the presence or absence of such renal excretory tubes opening into the intestine appears to be a question FIG.
(From Lankester, "Limulus an Arachnid.) of adaptation to the changed physiological conditions of respiration, and not of morphological significance, since a pair of renal excretory tubes of this nature is found in certain Amphipod Crustacea (Talorchestia, &c.) which have abandoned a purely aquatic life.
It appears that the Malpighian tubes of Scorpio are developed from the mesenteron, viz.
that portion of the gut which is formed by the hypoblast, whereas in Hexapod insects the similar caecal tubes are developed from the proctodaeum or in -pushed portion of the gut which is formed from epiblast.
In fact it is not possible to maintain that the renal excretory tubes of the gut are of one common origin in the Arthropoda.
In other words, the Malpighian tubes of the terrestrial Arachnida are homoplastic with those of Hexapoda and Myriapoda, and not homogenetic with them.
In the same and other leading forms a pair of much-coiled glandular tubes, the coxal glands (coelomocoels in origin), is found with a duct opening on the coxa of the fifth pair of appendages of the prosoma.
The gonadial tubes (gonocoels or gonadial coelom) are originally reticular and paired, though they may be reduced to a simpler condition.
In specialized forms these pulmonary sacs are wholly or partly replaced by tracheal tubes.
63,stg), as in the Amblypygi, or with the posterior pair, rarely the anterior pair as well, replaced by tracheal tubes.
The posterior pulmonary sacs (except in Hypochilus) replaced by tracheal tubes; the anterior and posterior pairs replaced by tracheal tubes in the Caponiidae.
Respiratory organs in the form of tracheal tubes opening by a pair of stigmata in the 2nd and 3rd somites of the opisthosoma.
In longer tubes a similar disturbance would be caused by a proportionally less difference of temperature.
Leber experimented with several chemical compounds to find what reaction they had on these cells; by using fine glass tubes sealed at the outer end and containing a chemical substance, and by introducing the open end into the blood vessels he found that the leucocytes were attracted - positive chemiotaxis - by the various compounds of mercury, copper, turpentin, and other substances.
Experiments on a short section of the line were made in 1900, and later schemes were set on foot to electrify the District system and bring under one general control this railway, other lines in deep level " tubes " between Baker Street and Waterloo, between Charing Cross, Euston and Hampstead, and between Hammersmith, Brompton, Piccadilly, King's Cross and Finsbury Park, and the London United Tramways Company.
Deeplevel electric railways (" tubes "), communicating with the surface by lifts, were already familiar in London.
Mile of Warsaw in 1828, who termed it a "hydrostatic air-pump without cylinders, taps, lids or stoppers," this is attained by using, both for the inlet and the outlet, vertical capillary glass tubes, soldered, the former to somewhere near the bottom, the latter to the top of the vessel.
These tubes, being more than 30 in.
Owing to this property, tubes or canes can be produced with a square, oblong, oval or triangular section.
The glass tubes, therefore, from which the X-ray bulbs are to be fashioned, must not contain any of these oxides, whereas the glass used for making the funnel-shaped shields, which direct the rays upon the patient and at the same time protect the hands of the operator from the action of the rays, must contain a large proportion of lead.
His object was to measure the contracted part of a fluid vein, to examine the phenomena attendant on additional tubes, and to investigate the form of the fluid vein and the results obtained when different forms of orifices are employed.
But this competition among inventors, whatever the incentive, has not been without benefit, because to-day, by means of very simple improvements in details, such as the addition of circulators and increased area of connexions, what may be taken to be the standard type of multiple-effect evaporator (that is to say, vertical vacuum pans fitted with vertical heating tubes, through which passes the liquor to be treated, and outside of which the steam or vapour circulates) evaporates nearly double the quantity of water per square foot of heating surface per hour which was evaporated by apparatus in use so recently as 1885 - and this without any increase in the steam pressure.
It is obviously easier to brush out and clean vertical tubes open at both ends, and about 6 ft.
long, on which the scale has already been loosened by the aid of boiling with dilute muriatic acid or a weak solution of caustic soda in water, than it is to clean either the inside or the outside of horizontal tubes more than double the length.
On passing the vapour through red-hot tubes it yields anthracene and toluene.
These cells are f - - imbedded in the peri pheral parenchyma, E"- and lead into convo luted excretory tubes _ that form an anasto- - mosis opening to the exterior by a pore at the " hinder " end of the body.
The excretory tubes, the nervous system, and the parenchyma and integument are continuous from one end of the worm to the other.
sodium nitrite, ethyl nitrite, amyl nitrite) cause relaxation of involuntary muscular fibre and therefore relieve the asthmatic attacks, which depend upon spasm of the involuntary muscles in the bronchial tubes.
The best cigarettes, however, are made by hand; the tobacco leaves are selected and hand-cut, and the paper tubes are filled by hand.
This head slides freely in the cast iron tubes, and is connected by a copper rod with one of the terminals of the dynamo supplying the current.
The vapours pass between the inner and outer tubes.
It consists of a number of tubes mounted vertically on a horizontal circular disk which rotates about a vertical axis in a cylindrical vessel.
This vessel has two tubulures: through one the end of the condenser projects so as to be over one of the receiving tubes; the other leads to the pump. By rotating the disk the tubes may be successively brought under the end of the condenser.
In the Le Bel-Henninger form a series of bulbs are connected consecutively by means of syphon tubes (b) and having platinum gauzes (a) at the constrictions, so that when a certain amount of liquid collects in any one bulb it syphons over into the next lower bulb.
A more general designation is "pyrogenic processes," which also includes such operations as leading vapours through red-hot tubes and condensing the products.
In its more complete form a still has in addition the following fittings: - The dome is provided with openings to admit (I) the axis of the stirring gear (in some stills the stirring gear rotates on a horizontal axis which traverses the side and not the head of the still), (2) the inlet and outlet tubes of a closed steam coil, (3) a tube reaching to nearly the bottom of the still to carry live steam, (4) a tube to carry a thermometer, (5) one or more manholes for charging purposes, (6) sight-holes through which the operation can be watched, and (7) a safety valve.
A common type of condenser consists of a copper worm placed in a water bath; but more generally straight tubes of copper or cast iron which cross and recross a rectangular tank are employed, since this form is more readily repaired and cleansed.
The more volatile vapours pass over to the condensing plant, while the less volatile ones condense in the bulbs and are returned to the column at varying heights by means of connecting tubes.
The condenser consists of a vertical cylinder having manifolds at the head and foot and through which a number of tubes pass.
the Weir, the condensing water circulates upwards through the tubes; in others, e.g.
the Quiggins, the water circulates around the tubes.
Various forms of the tubes have been adopted.
In the Pape-Henneberg condenser, which has been adopted in the German navy, they are oval in section and tend to become circular under the pressure of the steam; this alteration in shape makes the tubes self-scaling.
In his process a current was passed through a tank divided into two or three cells by porous partitions, hoods and tubes were arranged to carry off chlorine and hydrogen respectively, and the whole was heated to r20° F.
tubes were employed.
Faraday introduced the important and useful conception of lines and tubes of electric force.
If we consider lines of electric force to be drawn from the boundaries of these areas, they will cut up the space round the conductor into tubular surfaces called tubes of electric force, and each tube will spring from an area of the conductor carrying a unit electric charge.
Hence the charge on the conductor can be measured by the number of unit electric tubes springing from it.
These enclosing surfaces, therefore, cut up the space into shells of potential, and divide up the tubes of force into electric cells.
Returning to the case of the charged body with the space around it cut up into electric cells by the tubes of force and shells of potential, it is obvious that the number of these cells is represented by the product QV, where Q is the charge and V the potential of the body in electrostatic units.
By the surface density of electrification on a conductor is meant the charge per unit of area, or the number of tubes of electric force which spring from unit area of its surface.
If we consider the charge of a conductor to be measured by the number of tubes of electric force which proceed from it, then, since each tube must end on some other conductor, the above statement is equivalent to saying that the charges at each end of a tube of electric force are equal.
We can then establish some important properties of these tubes and surfaces.
Let us suppose any other surface described in the electric field so as to cut the closel y compacted tubes.
Behind the digestive stomach are situated, as usual, intestine and rectum, and the number of kidney (Malpighian) tubes varies from only six to over a hundred, being usually great.
In the female, each ovary consists of a large number of ovarian tubes, in which swollen chambers containing the egg-cells alternate with smaller chambers enclosing nutrient material.
The acid gland consists of one, two or more tubes, with a cellular coat of several layers, opening into a reservoir whence the duct leads to the exterior.
A loop of plati num wire passed under these tubes serves to suspend the vessel from the balance arm.
Many variations of this apparatus are in use; in one of the commonest there are two cylindrical chambers, joined at the bottom, and each provided at the top with fine tubes bent at right angles; sometimes the inlet and outlet tubes are provided with caps.
This may be accomplished by using a vessel with a somewhat wide bottom, and inserting the substance so that it may be volatilized very rapidly, as, for example, in tubes of Wood's alloy, D and by filling the tube with hydrogen.
The vaporizing bulb A has fused about it a jacket B, provided with a condenser c. Two side tubes are fused on to the neck of A: the lower one leads to a mercury manometer M, and to the air by means of a cock C; the upper tube is provided with a rubber stopper through which a glass rod passes - this rod serves FIG.
In the second form, named after Robert Hare (1781-1858), professor of chemistry at the university of Pennsylvania, the liquids are drawn or aspirated up vertical tubes which have their lower ends placed in reservoirs containing the different liquids, and their upper ends connected to a common tube which is in communication with an aspirator for decreasing the pressure within the vertical tubes.
The heights to which the liquids rise, measured in each case by the distance between the surfaces in the reservoirs and in the tubes, are inversely proportional to the densities.
Usually there are four excretory (Malpighian) tubes; but there are only two in the Coccidae and none in the Aphidae.
Fundamental alterations were made upon them: their wooden tubes were replaced by tubes of metal; 1 Description de l'observatoire central de Pulkowa, p. 208.
The colour of sea-water as it is seen on board ship is most readily determined by comparison with the tints of Forel's xanthometer or colour scale, which consists of a series of glass tubes fixed like the rungs of a ladder in a frame and filled with a mixture of blue and yellow liquids in varying proportions.
The yellow solution is made up of i part of neutral potassium chromate in 199 parts of water, and to give the various degrees of the scale, 1, 2, 3, 4, &c.,% of the yellow solution is mixed with 99, 9 8, 97, 96, &c.,% of the blue in successive tubes.
Aitken with clear sea-water in long tubes leave no doubt on the subject.
Pettersson in 1894, two portions of sea-water are collected in glass tubes which have been exhausted of air, coated internally with mercuric chloride to prevent the putrefaction of any organisms, and sealed up beforehand.
The chilled brine enters through a central tube of small diameter, passes to the bottom of the outer one and rises through the latter to the surface, each system of tubes being connected above by a ring main with the circulating pumps.
The brine is cooled in a tank filled with spiral pipes, in which anhydrous ammonia, previously liquefied by compression, is vaporized in vacuo at the atmospheric temperature by the sensible heat of the returncurrent of brine, whose temperature has been slightly raised in its passage through the circulating tubes.
In another system introduced by the Mannesmann Tube Company the prop is made up of weldless steel tubes sliding telescopically one within the other, which are fixed at the right height by a screw clamp capable of carrying a load of 15 to 16 tons.
It consists of a hollow sheet iron drum formed by two conoidal tubes, united together FIG.
by numerous guide blades, dividing it up into a series of rectangular tubes of diminishing section, attached to a horizontal axle by cast iron bosses and wrought iron arms. The tubes at their smallest part are connected to a cast iron ring, io ft.
Ragot and others made burners in which two jets of acetylene, coming from two tubes placed some little distance apart, impinged and splayed each other out into a butterfly flame.
They are ridges of aeolian limestone plastered over by a thin layer of corals and other calcareous organisms. The very remarkable "serpuline atolls" are covered by a solid crust made of the convoluted tubes of serpulae and Vermetus, together with barnacles, mussels, nullipores, corallines and some true incrusting corals.
The breath directed horizontally across the open end, impinged against the sharp inner edge of the pipes, creating the regular series of pulses which generate the sound waves within the tubes.
When the air in the singing tube is singing, it forces the gas in the jet tube to vibrate in the same period and in such phase that at the nozzle the pressure in both tubes shall be the same.
It is evident that the pressure condition will be fulfilled only if the motions in the two tubes are in the same direction at the same time, closing into and opening out from the nodes together.
In both England and America in early braced bridges cast iron, generally in the form of tubes circular or octagonal in section, was used for compression members, and wrought iron for the tension members.
Each span has four steel double ribs of steel tubes butted and clasped by wrought iron couplings.
In 1703 Samuel Morland, in a paper read before the Royal Society, stated that the farina (pollen) is a congeries of seminal plants, one of which must be conveyed into every ovum or seed before it can become prolific. In this remarkable statement he seems to anticipate in part the discoveries afterwards made as to pollen tubes, and more particularly the peculiar views promulgated by Schleiden.
Amici discovered the existence of pollen tubes, and he was followed by A.
The latter traced the tubes as far as the nucleus of the ovule.
The U-shaped electrolytic vessel and the electrodes are made of an alloy of platinum-iridium, the limbs of the tube being closed by stoppers made of fluor-spar, and fitted with two lateral exit tubes for carrying off the gases evolved.
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.
Lepidopterid flowers, visited chiefly by Lepidoptera, which are able to reach the nectar concealed in deep, narrow tubes or spurs by means of their long slender proboscis.
When kept for some time in sealed tubes it changes to a yellowish liquid, from which a yellow flocculent substance gradually separates, and finally it suddenly solidifies to a dark red mass, which appears to be a polymeric form.
But he is also called treasurer; tubes were and there can be no doubt that his services were chiefly of a fiscal character.
A pair of coiled nephridial tubes (n) formed of a file of perforated `' drain-pipe "cells, with ciliated tag-like" flame "cells (f), open into a contractile bladder (bl), FIG.
Lacinularia racemovata and Conochilus form free floating aggregates, the eggs, as laid, hatching and the young settling among the approximated gelatinous tubes of the parents.
He was associated with Sir William Fairbairn in an important series of experiments on cast iron, and his help was sought by Robert Stephenson in regard to the forms and dimensions of the tubes for the Britannia bridge.
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 pair of renal tubes opening right and left, rather far forward on the sides of the body, are always present.
It, as in other Mollusca, is not a blood-space but develops from the coelom, and it communicates with the exterior by the pair of renal tubes.
Further than this, the part of the mantle-skirt bounding the two holes is frequently drawn out so as to form a pair of tubes which project from the shell (figs.
Arca and Pectunculus) the lateral processes which are set on the axis of the ctenidium are not lamellae, but are slightly flattened, very long tubes or hollow filaments.
intralamellar spongy growth becomes, the more do the original gillfilaments lose the character of blood-holding tubes, and tend to become dense elastic rods for the simple purpose of supporting the spongy growth.
From all parts of the pyriform sac narrow stalk-like tubes are given off, ending in abundant widely-spread branching glandular caeca, which form the essential renal secreting apparatus.
The stone-flies further resemble the Orthoptera in their numerous Malpighian excretory tubes, which vary in number from twenty to sixty.
There are only six or eight Malpighian tubes - contrasting with the large number of these excretory organs found in the Orthoptera and Plecoptera.
The insects included in this order differ from those of the two preceding orders in their more condensed abdomens which bear no cerci, while the number of Malpighian tubes is reduced to four.
On the other hand, the reduced feelers, the numerous Malpighian tubes (40), the large complex eyes, the vestigial condition of the jaws, the excessive size of the fore-wings as compared with the hind-wings and their complex neuration with an enormous number of crossnervules are all specializations.
The winged insects resemble the May-flies in their short feelers and in the large number (50 to 60) of their Malpighian tubes, but differ most strikingly from those insects in their strong wellarmoured bodies, their powerful jaws adapted for a predaceous manner of life, and the close similarity of the hind-wings to the forewings.
Structurally the Neuroptera are distinguished by elongate feelers, a large, free prothorax, a labium with the inner lobes of the second maxillae fused together to form a median ligula, membranous, net-veined wings without hairy covering, those of the two pairs being usually alike, the absence of abdominal cerci, and the presence of six or eight Malpighian tubes.
The Fallopian tubes receive the ova and carry them to the uterus.
The base of the triangle is upward, and at each lateral angle one of the Fallopian tubes opens.
The epoophoron or parovarium is a collection of short tubes which radiate from the upper border of the ovary when the broad ligament is pulled out as in fig.
Near the ovary the tubes are closed, but nearer the Fal lopian tube they open into another tube which is nearly at right angles to them, and which runs toward the uterus, though in the human subject is generally lost before reaching that organ.
About the fifth week of human embryonic life the tunica albuginea appears in the male, from which septa grow to divide the testis into lobules, while the epithelial cords form the seminiferous tubes, though these do not gain a lumen until just before puberty.
The laboratory form in common use consists of a bellows worked by either hand or foot, and a special type of gas burner formed of two concentric tubes, one conveying the blast, the other the gas; the supply of air and gas being regulated by stopcocks.
In the Dibranchia true nephridia have not been detected in the embryo, nor has it been shown that the genital ducts are derived from the renal tubes.
Gases, like atmospheric air, hydrogen or carbon dioxide do not become luminous if they are placed in tubes, even when heated up far beyond white heat as in the electric furnace.
It is only recently that owing to the introduction of carbon tubes heated electrically the excitement of the luminous vibrations of molecules by temperature alone has become an effective method for the study of their spectra even in the case of metals.
For the investigation of the spectra of gases at reduced pressures the so-called Plucker tubes (more generally but incorrectly called Geissler tubes) are in common use.
To explain this great variability of spectroscopic effects we may either adopt the view that molecular aggregates of semi-stable nature may be found in vacuum tubes, or that a molecule may gain or lose one or more additional electrons and thus form new vibrating systems. It seemed that an important guide to clear our notions in this direction could be obtained through the discovery of J.
Phosphorescence (q.v.) can only be here alluded to in order to draw attention to the phenomena studied by Sir William Crookes and others in vacuum tubes.
The stand carries three tubes: the collimator, observing telescope and scale telescope.
The peripheral paren chyma gives rise to protonephridia, that is to coiled tubes commencing in pyriform cells containing a flame-like bundle of cilia and provided with branched outgrowths, and communicating with the exterior by long convoluted canals which open at the surface of the body.
The final arrest is due to paralysis of the respiratory centre in the medulla oblongata, hastened by a quasi-asthmatic contraction of the non-striped muscular tissue in the bronchial tubes, and by a "water-logging" of the lungs due to an increase in the amount of bronchial secretion.
It may be compared directly with that of the pure solvent, as the vapourpressure of a pure liquid is determined, by placing solvent and solution respectively above the mercury in two barometer tubes, and comparing the depressions of the mercury with the height of a dry barometer at the same temperature.
1) standing over a large quantity of weak alkali B, and the current was conveyed in wires insulated by U-shaped glass tubes CC passing through the liquid and round the mouth of the test-tube.
This may consist of a glass sphere of 50 litres' capacity, into the neck of which, presented downwards, the necessary tubes are fitted.
The metal in the form of thin turnings is charged into hard glass or iron tubes heated to a full red in a combustion furnace.
p. 331, 1900): - The glow obtained in vacuum tubes is highly characteristic, whether as seen directly or as analysed by the spectroscope.
This consists of a series of vertical earthenware condensing tubes through which compressed air is passed in order to reduce the quantity of nitrogen peroxide to a minimum.
jaws under Hexapoda); in the presence of a large number of excretory (Malpighian) tubes; in the firm texture of the forewings; in the presence of appendages (cerci) on the tenth abdominal segment; and in the absence of a metamorphosis, the young insect after hatching closely resembling the parent.
The telescopic mast consists of 8 tubes.
The other six are connected to each other and to the lowest one by wire cables and pulleys in such a way that when the cable which connects the two lowest tubes is wound in by means of a winch, each of the tubes except the fixed one will rise within the next one through the same distance.
The very large single spores of Pertusaria have been shown to contain numerous nuclei and when they germinate develop a large number of germ tubes.
The water-tube type, with multiple waterways, consists of a number of separate tubes j oined together in various ways.
Others are built with the tubes arranged horizontally, and are known as horizontal tubular boilers.
In case of adhesive clayey subsoil this can generally be secured by placing over the sloping bottom a good layer of coarse rubbly material, communicating with a drain in front to carry off the water, while earthenware drain tubes may be laid beneath the rubble from 8 to To ft.
Large Wimshurst multiple plate influence machines are often used instead of induction coils for exciting Rntgen ray tubes in medical work.
fungus, a mushroom), the botanical name covering in the broad sense all the lower cellular Cryptogams devoid of chlorophyll, which arise from spores, and the thallus of which is either unicellular or composed of branched or unbranched tubes or cell-filaments (hyphae) with apical growth, or of more or less complex wefted sheets or tissue-like masses of such (mycelium).
Such hyphae may be multicellular, or they may consist of simple tubes with numerous nuclei and no septa (Phycomycetes), and are then non-cellular.
Latex-tubes abound in the tissues of Lactarius, Stereum, Mycena, Fistulina, filled with white or coloured milky fluids, and Istvanffvi has shown that similar tubes with fluid or oily contents are widely spread in other Hymenomycetes.
Sometimes fatty oil or watery sap is found in swollen hyphal ends, or such tubes contain coloured sap. Cystidia and paraphyses may be also classed here.
The conidia are fragrant and are carried by bees to the stigma of the bilberry; here they germinate with the pollen and the hyphae pass with the pollen tubes down the style; the former infect the ovules and produce sclerotia, therein reducing the fruits to a mummified condition.
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 eye end of the telescope tube is removed - a counterpoise to the object end being substituted in its place - and a prism is inserted at the intersection of the visual axis with the transit axis, so that the rays from the object-glass may be reflected through one of the tubes of the transit axis to an eye-piece in the pivot of this tube.
For rock drills, and revolving saws for stone cutting, either diamond, bort or carbonado is employed, set in steel tubes, disks or bands.
The women wore two bronze pins, a bracelet on each arm, amber ornaments and a necklace of bronze tubes in spirals.
The height has also been calculated on the hypothesis that auroral light has its source where the atmospheric pressure is similar to that at which most brilliancy is observed when electric discharges pass in vacuum tubes.
They serve as channels by which the reproductive cells leave the body, and they are sometimes spoken of as "brown tubes."
The Ulvaceae, the thallus of which consists of external form as an expanded Coprinus, Neomeris simulates the laminae, one or more cells thick, or hollow tubes, probably represent fertile shoot of Equisetum with its densely packed whorled branches, a still more advanced stage in the passage of a colony into a multiand in Microdictyon, Anadyomene, Struvea and Boodlea the branches, cellular plant.
In Nereocystis and Macrocystis a zone of tubes occurs, which present the appearance of sieve-tubes even to the eventual obliteration of the perforations by a callus.
The filaments arising from the carpogonia grow into long thin tubes, which fuse with special cells rich in protoplasm contents; and from these points issue isolated tufts of sporogenous filaments, several of which may form the product of one fertilized female cell.
A case in point is the employment of hydraulic lime in place of Portland cement as grouting outside the cast-iron tubes used for lining tunnels made by the shield system.
When heated with alcohol in sealed tubes, it yields carbamic esters; with alcohol and carbon bisulphide at Ioo° C., carbon dioxide is liberated and ammonium sulphocyanide is formed.
This work also requires frequent annealing, for otherwise the wires or tubes would rupture.
Even hard steel is treated in this way to form tubes for the highest hydraulic and steam pressures.
BOLETUS, a well-marked genus of fungi (order Polyporeae), characterized by the central stem, the cap or pileus, the soft, fleshy tissue, and the vertical, closely-packed tubes or pores which cover the under surface of the pileus and are easily detachable.
For this purpose they are made by Moscicki in the form of glass tubes partly coated by silver chemically deposited on the glass on the inner and outer surfaces.
The tubes have walls thicker at the ends than in the middle, as the tendency to puncture the glass is greatest at the edges of the coatings.
When glass tubes are used it is better to employ tubes thicker at the ends than in the middle, as it has been found that when the safe voltage is exceeded and the glass gives way under electric strain, the piercing of the glass nearly always takes place at the edges of the tin foil.
For the purpose of a standard condenser a number of concentric metal tubes may be arranged on an insulating stand, alternate tubes being connected together.
One coating of the condenser is formed by one set of tubes and the other by the other set, the air between being the dielectric. Paraffin oil or any liquid dielectric of constant inductivity may replace the air.
It is extremely volatile, boiling at 12.5° C. (54.5° F.), and is therefore a gas at ordinary room temperatures; it is stored in glass tubes fitted with screwcapped nozzles.
Milne-Edwards, lodges in tubes of timber or bits of hollow reed.
The forward-directed exopods either act as valves or form a tube (rarely two tubes), protensile and retractile, for regulating egress of water from the branchial regions.
Contiguous stalactites are often inwrapped thus till they assume an almost globular form, through which by making a section the primary tubes appear.
Pasteur filled glass tubes entirely with new wine and then sealed them up. It was found that wine so treated remained unchanged in taste and flavour for years.
On the other hand, he filled some other tubes partly with wine, the remaining space being occupied by air.
By various experiments with liquids in tubes he found this power was nearly unity.
In this scheme large turbines were placed at the bottom of hydraulic fall tubes 150 ft.
It has long been known that air and other gases at the pressure of the atmosphere were very perfect insulators, but that when they were rarefied and contained in glass tubes with platinum electrodes sealed through the glass, electricity could be passed through them under sufficient electromotive force and produced a luminous appearance known as the electric glow discharge.
The so-called vacuum tubes constructed by H.
The substance which determines the form of a column of air is demonstrabl y indifferent for the timbre or quality of tone so long as the sides of the tubes are equally elastic and rigid.
This disease is due to the presence of large numbers of Bacillus solanacearum in the tubes through which water is conveyed to the leaves from the roots.
The action between the capillary tube and the water has been called capillary action, and the name has been extended to many other phenomena which have been found to depend on properties of liquids and solids similar to those which cause water to rise in capillary tubes.
p. 551), Leonardo da Vinci must be considered as the discoverer of capillary phenomena, but the first accurate observations of the capillary action of tubes and glass plates were made by Francis Hawksbee (Physico-Mechanical Experiments, London, 1709, pp. 13916 9; and Phil.
He observed that the effect was the same in thick tubes as in thin, and concluded that only those particles of the glass which are very near the surface have any influence on the phenomenon.
From this he showed that the rise of the liquid in tubes of the same substance is inversely proportional to their radii.
des Sciences, 1787, p. 506) asserted that " by supposing the adherence of the particles of a fluid to have a sensible effect only at the surface itself and in the direction of the surface it would be easy to determine the curvature of the surfaces of fluids in the neighbourhood of the solid boundaries which contain them; that these surfaces would be linteariae of which the tension, constant in all directions, would be everywhere equal to the adherence of two particles, and the phenomena of capillary tubes would then present nothing which could not be determined by analysis."
This assumption, however, does not appear to be verified by the experiments of Brunner and Wolff on the rise of water in tubes at different temperatures.
For All Fluids And For All Similar Tubes Similarly Wetted, The Weight Of A Drop Would Then Be Proportional Not Only To The Diameter Of The Tube, But Also To The Superficial Tension, And It Would Be Independent Of The Density.
In the preceding table, applicable to thin-walled tubes, the first column gives the values of T/gva', and the second column those of gM/Ta, all the quantities concerned being in C.G.S.
Relation Of Surface-Tension To Temperature It appears from the experiments of Brunner and of Wolf on the ascent of water in tubes that at the temperature t° centigrade T =75.20 (I -0.00187t) (Brunner); =76 08 (i-o o02t-Po ooOo0415t 2), for a tube .02346cm.diameter (Wolf); = 77.34(1 -o oo181t), for a tube 03098 cm.
The media are used either in a fluid or solid condition, the latter being obtained by a process of coagulation, or by the addition of a gelatinizing agent, and are placed in glass tubes or flasks plugged with cotton-wool.
The tubes, after being inoculated, are kept at the temperature of the body until growth appears.
Subsequent cultures or, as they are called, " subcultures," may be made by inoculating fresh tubes, and in this way growth may be maintained often for an indefinite period.
A few months after his return, through Germany, to London in 1815, he was induced to take up the question of constructing a miner's safety lamp. Experiments with samples of fire-damp sent from Newcastle soon taught him that "explosive mixtures of mine-damp will not pass through small apertures or tubes"; and in a paper read before the Royal Society on the 9th of November he showed that metallic tubes, being better conductors of heat, were superior to glass ones, and explained that the heat lost by contact with a large cooling surface brought the temperature of the first portions of gas exploded below that required for the firing of the other portions.
Two further papers read in January 1816 explained the employment of wire gauze instead of narrow tubes, and later in the year the safety lamps were brought into use in the mines.
Braun (Ber., 1904, 37, p. 2915) showed that benzoyl piperidine, when heated with phosphorus pentachloride to 200° C. in sealed tubes, yields benzonitrile, and pentamethylene dichloride, thus leading to a simple method of preparing pentamethylene compounds.
Into this same cloacal chamber open ventrally a pair of ciliated tubes communicating by funnels with the coelom (Nansen and Wheeler); these are possibly nephridia, and excretory in function.
The water was contained in about 2000 bent copper tubes, only s in.
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.
17, C, z and z'); they then grow into long tubes or proembryos, which make their way towards the prothallus (C, z'), and eventually embryos are formed from the ends of the proembryo tubes.
The megaspore of Welwitschia is filled with a prothallus-tissue before fertilization, and some of the prothallus-cells function as egg-cells; these grow upwards as long tubes into the apical region of the nucellus, where they come into contact with the pollen-tubes.
It is usually sent on the market in the form of sticks, which were at one time prepared by sucking the molten material up glass tubes; but the dangers to the workmen and other disadvantages of this method have led to its replacement by a continuous process, in which the phosphorus leaves the melting-pot for a pipe surrounded by water, in which it solidifies and can be removed as a continuous rod.
It remains colourless in vacuum tubes in the dark, but on exposure it rapidly turns yellow.
Ann., 1832, 24, p. 151) from phosphine and hydrobromic acid; it also results when phosphorus is heated with hydrobromic acid to 100120° C. in sealed tubes (Damoiseau, Bull.
The oxide P 2 0 was obtained by Besson (Comptes rendus, 1897, 124, p. 763; 1901, pp. 132, 1556) by heating a mixture of phosphonium bromide and phosphorus oxychoride in sealed tubes to 50°.
of the cast-iron cylinders forming the well was provided with about 660 small orifices lined with gun-metal tubes or rings, each armed with numerous thicknesses of copper wire gauze, and temporarily closed with screwed plugs.
In Clavularia and its allies each outgrowth contains several solenia, and the outgrowths may take the form of flat expansions, composed of a number of solenial tubes felted together to form a lamellar surface of attachment.
B A, Portion of the surface of a colony of Heliopora coerulea magnified, showing two calices and the surrounding coenenchymal tubes.
Z', the distal, and Z 2, the proximal or intracalicular portion of the zooid; ec, ectoderm; ct, coenenchymal tubes; sp, superficial network of solenia.
tubes, known as the coenenchymal tubes (fig.
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.
The cavities both of the calices and coenenchymal tubes of Heliopora are closed below by horizontal partitions or tabulae, hence the genus was formerly included in the group Tabulata, and was supposed to belong to the madreporarian corals, both because of its lamellar skeleton, which resembles that of a Ma.drepore, and because each calicle has from twelve to fifteen radial partitions or septa projecting into its cavity.
In Heliolites porosus the colonies had the form of spheroidal masses; the calices were furnished with twelve pseudosepta, and the coenenchymal tubes were more or less regularly hexagonal.
- Tentacles simple or branched, never peltate; calcareous ring well developed, often bilaterally symmetrical; retractor muscles usually present; stone-canal opens internally; genital tubes in right and left tufts.
It consists of two vertical tubes provided with feet and connected at the bottom by flexible rubber tubing.
To use the apparatus, the measuring tube is completely filled with water by pouring water into both tubes, raising the level tube until water overflows at the stopcock, which is then turned.
The volume of the gas in the measuring tube is determined by bringing the water in both tubes to the same level, and reading the graduation on the tube, avoiding parallax and the other errors associated with recording the coincidence of a graduation with a (By permission of Messrs Baird & Tatlock.) FIG.
The cylinder in direct communication with the capillary is filled with glass tubes so as to expose a larger surface of the absorbing solution to the gas.
a is a vertical steam boiler, heated by a central shaft filled with coke, with superheating tubes b passing through the central shaft.
A brief notice must suffice of the structure and history of the Eyes, the Tracheae and the so-called Malpighian tubes of Arthropoda, though special importance attaches to each in regard to the determination of the affinities of the various animals included in this great sub-phylum.
Tracheae are essentially tubes like bloodvessels - apparently formed from the same tissue elements as bloodvessels - which contain air in place of blood, and usually communicate by definite orifices, the tracheal stigmata, with the atmosphere.
(Modified from Watase.) patus and the Diplopods they consist of bunches of fine tubes which do not branch but diverge from one another; the chitinous lining is smooth.
In these forms the chitinous lining of the tubes is thickened by a closeset spiral ridge similar to the spiral thickening of the cellulose wall of the spiral vessels of plants.
It is a noteworthy fact that other tubes in these same terrestrial Arthropoda - namely, the ducts of glands - are similarly strengthened by a chitinous cuticle, and that a spiral or annular thickening of the cuticle is developed in them also.
It seems that we have to suppose that the vasifactive tissue of Arthropoda can readily take the form of air-holding instead of blood-holding tubes, and that this somewhat startling change in its character has taken place independently in several instances - viz.
This name is applied to the numerous fine caecal tubes of noticeable length developed from the proctodaeal invert of ectodermal origin in Hexapods.
These tubes are shown to excrete nitrogenous waste products similar to uric acid.
Tubes of renal excretory function in a like position occur in most terrestrial Arthropoda - viz.
But the conclusion that all such tubes are identical in essential character seems to be without foundation.
The Malpighian tubes of Hexapods are outgrowths of the proctodaeum, but those of Scorpion and the Amphipod Crustacea are part of the metenteron or endodermal gut, though originating near its junction with the proctodaeum.
Hence the presence or absence of such tubes cannot be used as an argument as to affinity without some discrimination.
The Scorpion's so-called Malpighian tubes are not the same organs as those so named in the other Tracheata.
Such renal caecal tubes seem to be readily evolved from either metenteron or proctodaeum when the conditions of the out-wash of nitrogenous waste-products are changed by the transference from aquatic to terrestrial life.
With the characters of the grade: add the presence within the body of fine unbranched tracheal tubes, devoid of spiral thickening, opening to the exterior by numerous irregularly scattered tracheal pits.
In Scutigera there are seven unpaired dorsal stigmata, each leading into a sac whence a number of air-holding tubes project into the pericardial blood-sinus.
Renal caecal tubes (Malpighian tubes) open into the proctodaeum.
Renal excretory caeca (Malpighian tubes) are developed from the proctodaeum (not from mesenteron as in scorpion and Amphipoda).
Phoronis is often gregarious, the tubes which it secretes being sometimes intertwined in an inextricable mass.
The physiological action of stramonium resembles that of belladonna, except that stramonium relaxes to a greater extent the unstriped muscle of the bronchial tubes; for this reason it is used in asthma to relieve the bronchial spasm.
Here may be mentioned the guttural pouches, large airsacs from the Eustachian tubes, and lying behind the upper part of the pharynx, the function of which is also not understood.
- Section through a tracheal pit and diverging bundles of tracheal tubes taken transversely to the long axis of the body.
Internally it expands in the transverse plane, and from the expanded portion the tracheal tubes arise in diverging bundles.
The tracheae are minute tubes exhibiting a faint transverse striation which is probably the indication of a spiral fibre.
The ovaries consist of a pair of tubes closely applied together, and continued posteriorly into the oviducts.
This change is usually effected by mounting the objective and eyepiece on two telescoping tubes, so that by drawing apart or pushing in the tube length is increased or diminished at will.
The two tubes are inclined to one another at an angle of about 14°.
These spurs, tubes and sacs serve as receptacles for the secretion or containing of nectar.
The pollen-tube or tubes pass down the canal (fig.
"plant-lice," "blight," and "green-fly," belonging to the homopterous division of the order Hemiptera, with long antennae and legs, two-jointed, two-clawed tarsi, and usually a pair of abdominal tubes through which a waxy secretion is exuded.
These tubes were formerly supposed to secrete the sweet substance known as "honey-dew" so much sought after by ants; but this is now known to come from the alimentary canal.
The tissue is made up of large, unseptate, occasionally branching tubes, with an undulating vertical course, among which much smaller tubes are irregularly interwoven.
The concentric rings of growth, which form a characteristic feature, are due to periodic variations in the size of the larger tubes.
Penhallow maintains that these smaller tubes arise as branches from the larger, but other observers have failed to confirm this.
Storriei, from the Silurian (Wenlock) of South Wales, described by Barber, there is no sharp differentiation of the two kinds of tubes; they are rarely observed to branch, except in the gaps, which in this species are not radially directed.
Ortoni (Penhallow), from the Devonian of Canada, the tubes are quite uniform, and there are no spaces or concentric rings.
The tubes have their cavity dilated at intervals, and Penhallow has therefore compared them with the trumpet-hyphae of Laminariaceae, but no transverse septa are anywhere visible.
Aglossa, - Eustachian tubes united into a single ostium pharyngeum; no tongue.
Phaneroglossa, - Eustachian tubes separated; tongue present.
The lungs are long simple tubes in some of the perennibranchiate Caudata; they generally shorten or become cellular in the salamandrids, and attain their highest development in the Ecaudata, especially in such forms as the burrowing Pelobates.
The oviducts are long, usually more or less convoluted tubes which open posteriorly into the cloaca, while their anterior aperture is situated far forward, sometimes close to the root of the lung; their walls secrete a gelatinous substance which invests the ova as they descend.
Expectorants increase the bronchial secretions; antispasmodics relax the spasm of the muscular coat of the bronchial tubes, e.g.
Even under the most advantageous application, that of evaporation of water in a steam boiler where the gases of the fire have to travel through a great length of flues bounded by thin iron surfaces of great heat-absorbing capacity, the temperature of the current at the chimney is generally much above that required to maintain an active draught in the fireplace; and other tubes containing water, often in considerable numbers, forming the so-called fuel economizers, may often be interposed between the boiler and the chimney with marked advantage as regards saving of fuel.
Owing to the conditions of the work, which require the maintenance of a sensibly reducing atmosphere, they contain a very notable proportion of carbonic oxide, and are drawn off by large wrought iron tubes near the top of the furnace and conveyed by branch pipes to the different boilers and air-heating apparatus, which are now entirely heated by the combustion of such gases, or mixed with air and exploded in gas engines.
Armament: Four 5.5 -inch guns Three 3.1 inch aa guns and Six 21 - inch torpedo tubes in three carrying 12 Torpedos.
These are relatively low cost, plastic tubes which contain a prepared absorbent which can later be desorbed for analysis and measurement.
actinic tubes; the paddock a 125 MV light.
Close to the front opening of the Eustachian tubes are masses of tissue called adenoids.
Static tubular aerator a system in which air is blown into vertical tubes submerged in a liquid, promoting mixing and oxygen transfer.
The kit consists of reservoir pot, inner pot, exterior air pump, clay pebbles, delivery tubes and full instructions.
alien spaceships that appear to be totally made up out of tubes.
Dispense in 10 ml aliquots in appropriately sized capped tubes and sterilize at 121 °C for 15 minutes.
aluminum tubes for rockets in the 1980s.
Iraq has made several attempts to buy high-strength aluminum tubes used to enrich uranium for a nuclear weapon.
The report does note a minority of intelligence analysts believes the tubes are for conventional weapons, not a nuclear program.
annelid worms, their jaws, tubes, opercula and granules.
anther tubes have a collection of pollen grains at their tip.
A black card placed behind the tubes will also improve appearance.
automaton model, which simulates the propagation of lava tubes.
Instead of vacuum bagging, I plan to use truck tubes to apply pressure.
bimetal tubes In primary heat exchangers handling ammonia, plain steel tubes are frequently used.
To account for tubes banks of turned black after when he thought.
booby tubes (£ 17.95) are pack that can be microwaved or frozen to deliver a hot or cold compress for sore breasts.
In the focus groups, train fares were a particular bugbear: Train prices are unbelievable Tubes are better than trains.
Many had used oxygen tubes, even in the pressurized cabins.
calcium chloride guard tubes?
For example, you can easily see areas where there are vadose canyons or phreatic tubes.
What are the weights and carrying capacity of copper tubes?
Carbon nanotubes are graphite sheets of carbon nanotubes are graphite sheets of carbon which are rolled up to form tubes.
cathode ray tubes were curved for a good reason.
ICER - Materials recovery from waste cathode ray tubes (CRTs ).
The cells were collected by centrifugation, transferred to 50 ml tubes, resuspended in 30 ml binding buffer, and frozen.
centrifuge the tubes, appropriately 4 Determine the reaction grade.
centrifuge tubes are fixed to the rotor blades.
All samples, with the exception of the diffusion tubes, were analyzed using ion chromatography.
Minimal lighting is provided by UV tubes, lasers and a selection of old school coin-ops such as the original Galaxians and Star Wars.
Have your tubes tied, get the snip, wear a condom, take a pill, pull out, anything!
The Bassoon tubes spring up a little conical, and suddenly spread out wide at the top like a bell.
constriction of the bronchial tubes ).
cress seedlings in glass tubes of agar containing the metal ions.
Diving is conducted from a range of purpose built dhows and two RIBs, with fiber glassed tubes.
Sensors - These two units house the balanced diaphragms used to detect the pressure differences between the tubes.
diffusion tubes can also provide valuable data for Stage III.