How to use Thickness in a sentence
Borings show that the thickness of this group varies from 35 o ft.
The thickness varies from five to sixteen feet.
The seams vary in thickness.
In many Laminariaceae the thallus also grows regularly in thickness by division of its surface layer, adding to the subjacent permanent tissue and thus forming a secondary meristem.
It is evident that accurate knowledge of the character and structure of the rock-formations in petroliferous territories is of the greatest importance in enabling the expert to select favourable sites for drilling operations; hence on well-conducted petroleumproperties it is now customary to note the character and thickness of the strata perforated by the drill, so that a complete section may be prepared from the recorded data.Advertisement
Jamaica quassia is imported into England in logs several feet in length and often nearly one foot in thickness, consisting of pieces of the trunk and larger branches.
The plant has a well-developed main root (tap-root) and a single or branched leafy stem which is provided with a means of secondary increase in thickness.
The fibrous bands are generally formed towards the end of the years growth in thickness.
Potatoes give fair results when they are taken good care of, carrots grow to a thickness of IIin., while cabbage does poorly.
The bottom should slope towards the outer edge, where a drain should be cut, with an outlet, and on this sloping bottom should be laid a thickness of from 9 in.Advertisement
In 1865 Kowalevsky discovered that the organs of respiration consist of numerous pairs of gill-slits leading from the digestive canal through the thickness of the body-wall to the exterior.
The vascular system itself is quite peculiar, consisting of lacunae and channels destitute of endothelium, situated within the thickness of the basementmembrane of the body-wall, of the gut-wall and of the mesenteries.
The required thickness of the spread sheet is very often secured by the rubber-faced surfaces of two cloths being united before curing.
Very irregular surfaces may require the use of specially shaped anodes in order that the distance between the electrodes may be fairly uniform, otherwise the portion of the cathode lying nearest to the anode may receive an undue share of the current, and therefore a greater thickness of coat.
In dressing mica the "books" are split along the cleavage into sheets of the required thickness, and the sheets trimmed into rectangles with a sharp knife, shears or guillotine, stained and damaged portions being rejected.Advertisement
The valves are also in some species very unequal in their respective thickness, as may be seen in Productus (Daviesiella) 1 llangollensis, Davidsonia verneuilii, &c., and while the space allotted to the animal is very great in many species, as in Terebratula sphaeroidalis, it is very small in others belonging to Stro phomena, Leptaena, Chonetes, &c. The ventral valve is usually the thickest, and in some forms is six or seven times as great as the opposite one.
It forms gigantic deposits of almost constant thickness, embedded between a floor of limestone and a roof of porphyry.
At the best thickness To the bands are black, and not otherwise.
A thin sheet of magnetic matter magnetized normally to its surface in such a manner that the magnetization at any place is inversely proportional to the thickness h of the sheet at that place is called a magnetic shell; the constant product hI is the strength of the shell and is generally denoted by 4, or 4.
If the field is uniform, H=O/wd, where 0 is the rotation, d the thickness of the substance arranged as a plate at right angles to the direction of the field, and w Verdet's constant for the substance.Advertisement
The difference of the ballastic throws taken with the two coils measured the intensity of the field in the space around the iron, and it also enabled a correction to be made for the nonferrous space between the iron neck and the centre of the thickness of'the inner coil.
The tranverse electromotive force is equal to KCH/D, where C is the current, H the strength of the field, D the thickness of the metal, and K a constant which has been termed the rotatory power, or rotational coefficient.
This telson may enlarge, it may possibly even become internally and sternally developed as partially separate somites, and the tergum may remain without trace of somite formation, or, as appears to be the case in Limulus, the telson gives rise to a few well-marked somites (mesosoma and two others) and then enlarges without further trace of segmentation, whilst the chitinous integument which develops in increasing thickness on the terga as growth advances welds together the unsegmented telson and the somites in front of it, which were previ ously marked by separate tergal thickenings.
The Silurian scorpion Palaeophonus, differs, so far as obvious points are concerned, from a modern scorpion only in the thickness of its legs and in their terminating in strong spike-like joints, instead of being slight and provided with a pair of terminal claws.
The Dwyka conglomerate rarely attains any great thickness though forming wide outcrops.Advertisement
The function of a lens in forming an image is to compensate by its variable thickness the differences of phase which would otherwise exist between secondary waves arriving at the focal point from various parts of the aperture.
If, as in common flint-glass spectroscopes, there is only one dispersing substance, f Sy ds = Sµ.s, where s is simply the thickness traversed by the ray.
The former measures the thickness of the primary focal line, and the latter measures its curvature.
Even in the contrary case, the thickness of the plate must not exceed a certain limit, dependent upon the purity of the spectrum.
The formation of bands thus requires that the retarding plate be held upon the side already specified, so that zs be positive; and that the thickness of the plate (to which z is proportional) do not exceed a certain limit, which we may call 2T 0.Advertisement
If it be desired to see a given number of bands in the whole or in any part of the spectrum, the thickness of the retarding plate is thereby determined, independently of all other considerations.
The individual beds, seldom more than a few feet in thickness and sometimes only a few inches, are interstratified with an immense thickness of quartzites.
Near Reitzburg the coarse conglomerates reach a thickness of 400 ft.
It varies in thickness from 500 ft.
The thickness of the salt is unknown; the mines yield about 11,000 tons annually.Advertisement
With a number of holes the average thickness and probable extent of the deposit may be determined, at least approximately.
In the case of metalliferous deposits of varying thickness or irregular distribution the information from bore-holes is less satisfactory.
A large number of holes must be bored to obtain, even approximately, the average thickness and value of the ore and the shape and size of the ore bodies.
The method to be adopted will vary with the thickness and character of the deposit, with its inclination, and to some extent with the character of the enclosing rocks, the depth below the surface, and other conditions.
While it is always desirable to provide large working-places, the size of the working-place is limited by the thickness and Size of strength of the overlying beds forming the roof Working- or hanging wall of the mine.Advertisement
There is considerable thickness of old timber left from the working of the upper levels.
The working out of each floor is conducted much as if it were a bed of corresponding thickness.
In such cases preliminary surveys should be made to determine the thickness of rock over the proposed workings.
When the presence of underground bodies of water is known or suspected, advance bore-holes should radiate from the end of the advancing working place so as to give warning of the position of the body of water, these holes being of such length as to ensure a safe, thickness of solid rock.
Plate glass of the usual quality, which appears to be perfectly homogeneous when looked at in the ordinary way, is seen to be a mass of fine striae, when a considerable thickness is examined in parallel light.Advertisement
For the purpose of rendering this minute examination possible, opposite plane surfaces of the glass are ground approximately flat and polished, the faces to be polished being so chosen as to allow of a view through the greatest possible thickness of glass; thus in slabs the narrow edges are polished.
The latter kind is known as " flashed," and is universally employed in the case of colouring matters whose effect is so intense that in any usual thickness of glass they would cause almost entire opacity.
The width of the sheet or plate is regulated by moving guides which are placed in front of the roller and are pushed along by it, while its thickness is regulated by raising or lowering the roller relatively to the surface of the table.
To give an idea of what can be done in this way, it may be stated that gold can be beaten out to leaf of the thickness of - j g - mm.; and that platinum, by judicious work, can be drawn into wire 2?o o mm.
The amount of deposit laid over the land reaches a thickness of two or three feet in one season of warping, which is usually practised between March and October, advantage being taken of the spring tides during these months.Advertisement
The nitrate forms beds, varying in thickness from 6 in.
The material is supplied to the twisting machinery by an attendant, and formed into a cord of uniform thickness, twisted and wound on a drum by mechanism analogous to that used in rope-spinning.
Cheroots differ from ordinary cigars only in shape, being either in the form of a truncated cone, or of uniform thickness throughout, but always having both ends open and sharply cut across.
There are several varieties in cultivation, varying in the degree of hardihood, time of ripening, thickness of shell, size and other particulars.
Although of no great thickness it covers six-sevenths of the island, rising in a series of steps or platforms to a height of nearly 1 10o ft.
According to native report, the gorillas sleep on these beds, which are of sufficient thickness to raise them a foot or two above the ground, in a sitting posture, with the head inclined forwards on the breast.
The whole range is highly auriferous, and the thickness of the strata is not less than 10,000 ft.
Accordingly, the vessel was built so low in the water that the waves glided easily over its deck except at the middle, where was constructed a revolving turret 1 for the guns, and though the vessel's iron armour had a thickness of 1 in.
With regard to incised chiselling, the commonest form is kebori (hair-carving), which may be called engraving, the lines being of uniform thickness and depth.
Thus if Q is the surface density, S the thickness of the shell at any point, and p the assumed volume density of the matter of the shell, we have v =Abp. Then the quantity of electricity on any element of surface dS is A times the mass of the corresponding element of the shell; and if Q is the whole quantity of electricity on the ellipsoid, Q =A times the whole mass of the shell.
Except in the larger nuggets, which may be more or less angular, or at times even masses of crystals, with or without associated quartz or other rock, gold is generally found bean-shaped or in some other flattened form, the smallest particles being scales of scarcely appreciable thickness, which, from their small bulk as compared with their surface, subside very slowly when suspended in water, and are therefore readily carried away by a rapid current.
The formation is noted for its regularity as regards both the thickness and the gold-tenor of the ore-bearing reefs, in which respect it is unparalleled in the geology of the auriferous formations.
It is deposited from water, which bubbles up from a number of springs in the form of horizontal layers, which at first are thin crusts and can easily be broken, but gradually solidify and harden into blocks with a thickness of 7 to 8 in.
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.
The habitats which they affect are the hot, dry regions of tropical America, the aridity of which they are enabled to withstand in consequence of the thickness of their skin and the paucity of evaporating pores or stomata with which they are furnished, - these conditions not permitting the moisture they contain to be carried off too rapidly; the thick fleshy stems and branches contain a store of water.
Warburg in 1875 on the viscosity of gases; its effects would be corrected for, in general, by a slight effective addition to the thickness of the gaseous layer.
The amount of separation is very small, and depends on the thickness of the glass, the index of refraction and the focal length of the telescope.
Ice is a very poor conductor of heat and accordingly protects the surface of the water beneath from rapid cooling; hence new-formed pancake ice does not increase excessively in thickness in one winter, and even in the centre of the Arctic Basin the ice-covering only amounts to 6 or at most 9 ft.
Underneath is the true floor of the cave, a mass of homogeneous yellow clay, one metre in thickness.
The commencement of the Carboniferous period is marked by a mass of limestones known as the Carboniferous or Sequences Mountain Limestone,which contains a large assemblage of carbon- of marine fossils, and has a maximum thickness in iferous S.W.
These are also called the Upper Limestone Shale, a similar group being found in places below the limestone, and called the Lower Limestone Shale, or, in the north of England, the Tuedian group. Going northward the beds of limestone diminish in thickness, with a proportional increase in the intercalated sandstones and shales, until in Scotland they are entirely subordinate to a mass of coal-bearing strata, which forms the most productive members of the Scotch coalfields.
The Coal Measures, forming the third great member of the Carboniferous series, consist of alternations of shales and sandstones, with beds of coal and nodular ironstones, which together make up a thickness of many thousands of feet - from 12,000 to 14,000 ft.
The thickness of coal seams varies in Great Britain from a mere film to 35 or 40 ft.; but in the south of France and in India masses of coal are known up to 200 ft.
The thickness varies according to the pressure expected, but may be taken at from 4 to i 2 in.
The laying out of a colliery, after the coal has been won, by sinkings or levels, may be accomplished in various ways, according to the nature of the coal, its thickness and dip, and the extent of ground to be worked.
In the South Wales system of working, cross headings are driven from the main roads obliquely across the rise to get a sufficiently easy gradient for horse roads, and from these the stalls are opened out with a narrow entrance, in order to leave support on either side of the road, but afterwards widening to as great a breadth as the seam will allow, leaving pillars of a minimum thickness.
With careful packing it is estimated that the surface subsidence will not exceed 40% of the thickness of the seam removed, and will usually be considerably less.
Until the 9th century the only means for sighting cannon was by the " line of metal " - a line scored_ along the top of the gun, which, owing to the greater thickness of metal at the breech than at the muzzle, was not parallel to the axis.
This method is unconsciously adopted by the teacher who illustrates the equality of area of two geometrical figures by cutting them out of cardboard of uniform thickness and weighing them.
If the planes of one set divide it into m slabs of thickness h, and those of the other into n slabs of thickness k, so that H =mh, K = nk, then the values of x and of y for any ordinate may be denoted by xo+Oh and yo+Ok, and the length of the ordinate by uo, 0.
Allowance must of course be made for the thickness of the wood.
The cast bars are reduced to the thickness of the coin by repeated passages between rolls.
The reduction in thickness of the bars is accompanied by a slight increase in their width and a very great increase in their length, so that it is generally necessary to cut partly rolled bars into two parts to keep them of convenient dimensions.
In some mints the drag-bench or draw-bench is used after the rolls to equalize the thickness of the fillets.
When they have been reduced to the correct thickness they are examined by the " tryer," who cuts out one or two blanks from each fillet with a hand machine and weighs them on a delicate balance.
As the mean thickness of a sovereign is 0.0466 in., the remedy for weight corresponds to a difference of less than in.
The Columbia plateau consists of horizontal beds of lava having a total thickness of several thousand feet, and its surface has a general elevation of tow to 2000 ft.
The law that, caeteris paribus, n varies inversely as the thickness may be tested by forming a string of four lengths of the single thread used before, and consequently of double the thickness of the latter, when, for the same length and tension, the compound thread will exhibit double the number of ventral segments presented by the single thread.
The thickness of the arch is 4 ft.
In the case of the plate web there must be a considerable excess of material, partly to stiffen it against buckling and partly because an excess of thickness must be provided to reduce the effect of corrosion.
The thickness of the formation near London is about 400 ft., and at Sheppey it reaches 480 ft.
The thickness of the formation varies from 15 to 80 ft., but most commonly it is from 25 to 40 ft.
They consist chiefly of flint pebbles or of lightcoloured quartzose sand, the thickness being from 20 to 30 ft, and.
There is also a postern gate on the north side of the wall, and at its eastern extremity are two apertures in the thickness of the wall.
On electrolysis a layer of metallic calcium is formed at the lower end of this rod on the surface of the electrolyte; the rod is gradually raised, the thickness of the layer increases, and ultimately a rod of metallic calcium, forming, as it were, a continuation of the iron cathode, is obtained.
Frequently in districts where slates are much crumpled they are traversed by numerous quartz veins, which have a thickness varying from several inches up to many feet, and may occasionally be auriferous.
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.
Such veins often attain a thickness of several feet, and sometimes possess a columnar structure perpendicular to the enclosing walls; they are met with in the crystalline limestones and other Laurentian rocks of New York and Canada, in the gneisses of the Austrian Alps and the granulites of Ceylon.
A sheet of silver of a finer quality than standard, ranging in thickness from-+ 6 - in.
This was passed again and again between gradually approximated rollers, with occasional annealing, until the desired thickness had been attained.
The next event is a great growth in thickness of the gelatinous mesogloea, especially on the exumbral side; as a result the flattened coelenteron is still further compressed so that in certain spots its cavity is obliterated, and its exumbral and subumbral layers of endoderm come into contact and undergo concrescence.
Thickness of skin, masking the muscles, has been thought the cause of a peculiar heaviness in the outlines of body and face; the complexion varies from yellow-brown to chocolate (about 40 to 43 in the anthropological scale); eyes black; straight coarse glossy black hair; beard and moustache scanty.
It attains a thickness of 20 ft.
The Plateau province, next west of the southern Rocky Mountains, is characterized for the most part by large-textured forms, developed on a great thickness of nearly horizontal Palaeozoic, The Plateau Mesozoic and Tertiary formations, and by a dry climate.
The aggregate thickness of the Proterozoic systems in the Lake Superior region is several miles, as usually computed, but there are obvious difficulties in determining the thickness of such great systems, especially when they are mtich metamorphosed.
The thickness of the system has been estimated at 10,009 to 12,000 ft.
In Wisconsin, where the Upper Cambrian only is present, the thickness is about Iooo ft.
The greater thickness in the east appears to be due in part to the fact that an extensive area of land, Appalachia.
The greatness of the thickness, as it has been measured, is also due in part to the oblique position in which the beds of sediment were originally deposited.
The thickness of the system varies from point to point, being greatest in the Appalachian Mountains, and much less in the interior.
In the interior the thickness of the system is less than 1000 ft.
Like the earlier Palaeozoic systems, the Devonian attains its greatest known thickness in the Appalachian Mountains, where sediments from the lands of pre-Cambrian rock to the east accumulated in quantity.
Here clastic rocks predominate, while limestone is more abundant in the interior, If the maximum thicknesses of all Devonian formations be added together, the total for the system is as much as 15,000 ft.; but such a thickness is not found in any one pluce.
The system ranges in thickness from nearly 5000 ft.
The system has its maximum known thickness in Texas, where it is said to be 7000 ft.
Triassic SystemThis system has but limited representation in the eastern part of the United States, being known only east of the Appalachian Mountains in an area which was land throughout most of the Palaeozoic era, hut which was deformed when the eastern mountains were developed at the close of the Palaeozoic. In the troughs formed in its surface during this time of deformation, sediments of great thickness accumulated during the Triassic period.
In the United States, marine Shastan beds are restricted to the area west of the Sierras, but they here have great thickness.
If maximum thicknesses of its several parts in different localities, as usually measured, are added together, the total would approach or reach 25,000 ft.; but the strata of any one region have scarcely more than half this thickness, and the average is much less.
The system has been reported to have a thickness of more than 7000 ft.
The system is wanting in northern California and southern Oregon, but appears again farther north, and has great development in Oregon, where its thickness has been estimated at more than 10,000 ft.
As in other comparable cases, this figure does not make allowance for the oblique attitude in which the sediments were deposited, and should not be construed to mean the vertical thickness of the system.
In \Vashington the Eocene is represented by the Puget series of brackish water beds, with an estimated thickness exceeding that of the marine formations of Oregon.
The thickness of the system in the west is great, the formations of each of the several stages mentioned above running into thousands of feet, as thicknesses are commonly measured.
The Miocene of the Atlantic and Gulf regions nowhere attains great thickness.
The marine Pliocene of the continent has its greatest development in California (the Merced series, peninsula of San Francisco), where it is assigned a maximum thickness of nearly 6000 ft., and possibly as much as 13,000 ft.
It is entered from the east by a passage, on each side of which there is a small chamber constructed within the thickness of the wall.
The last is secreted by the whole surface of the mantle except the border, and additions to its thickness continue to be made through life.
These two layers, therefore, when once formed cannot increase in thickness; as the mantle grows in extent its border passes beyond the formed parts of the two outer layers, and the latter are covered internally by a deposit of nacreous matter.
The filaments take on a secondary grouping, the surface of the lamella being thrown into a series of halfcylindrical ridges, each consisting of ten or twenty filaments; a filament of much greater strength and thickness than the others may be placed between each pair of groups.
Thus the growth of the shell in extent is due to additions to the prismatic layer at the edge, its growth in thickness to new layers of nacre deposited on its inner surface.
In the cold regions of the northern lowlands peat occurs in beds of immense thickness.
As the outer flossy threads and the inner vests are not reelable, it is difficult to estimate the total length of thread produced by the silkworm, but the portion reeled varies in length and thickness, according to the condition and robustness of the cocoon, in some breeds giving a result as low as Soo metres, and in others 900 to 1200 metres.
As the reeling proceeds the reeler has to give the most careful attention to the thickness of the strand being produced, and to introduce new cocoons in place of any from which the reelable silk has become exhausted.
In the case of prisms the resolving power ist (dµ/dX), where t is the effective thickness of the medium traversed by the ray.
If 1 2 and t l are thicknesses traversed by the extreme rays, t = t 2 - t,, and if, as is usually the case, the prism is filled right up to its refraction cap, = o, and t becomes equal to the greatest thickness of the medium which is made use of.
The same author proved that a sufficient thickness of layer raised the radiation to that of a black body in agreement with Kirchhoff's law.
C, Chambers in the thickness of the wall opening out of the gallery.
On the south is a gallery built in the thickness of the wall, and roofed by projecting courses of stone; and chambers or storehouses open out of this gallery.
The needle is peculiarly poised, with its point of suspension a little below its centre of gravity, and is exceedingly sensitive; it is seldom more than an inch in length, and is less than a line in thickness.
In order to reduce the thickness of the walls and floor he conceived the idea of strengthening them by building in a network of iron rods.
In the Matrai system thin wires are used instead of rods, and are securely fastened to rolled steel joists, which form the beams on which the slabs rest; moreover, the wires instead of being stretched tight from side to side of the slab are allowed to sag as much as the thickness of the concrete will allow.
The resemblance also extends to the general form of the body and to the length and thickness of the wings and antennae.
This genus is especially abundant in Eocene Limestones, which attain great thickness around the Mediterranean basin; the Pyramids of Egypt are built of it.
The mooruk, or Bennett's cassowary (Casuarius Bennettii), is a shorter and more robust bird, approaching in the thickness of its legs to the moas.
As dryness is favourable to an increase of heat, such walls should be either built hollow or packed behind to the thickness of 3 or 4 ft.
The method in the latter case is to select roots averaging the thickness of the little finger, to cut these into lengths of about 3 or 4 in., and to plant them FIG.
Many of the free-growing soft-wooded plants may also be grown from cuttings of single joints of the young wood, where rapid increase is desired; and in the case of opposite-leaved plants two cuttings may often be made from one joint by splitting the stem longitudinally, each cutting consisting of a leaf and a perfect bud attached to half the thickness of the stem.
Fruit trees and shrubs may be set out; but, if planting is deferred to the last of the month, the ground around the roots should be mulched to the thickness of 3 or 4 in.
In this case the carbonaceous beds-coal-seams-naturally appealed most strongly to the imagination, and the name is a good one, notwithstanding the fact that coal-seams occupy but a small fraction of the total thickness of the Carboniferous system; and although subsequent investigations have demonstrated the existence of coal in other geological formations, in none of these does it play so prominent a part.
The great variety of conditions under which the sediments and limestones were formed naturally produced corresponding inequalities in the thickness.
In the Eurasian land area the greatest thickness of Carboniferous rocks is in the west; in North America it is in the east.
In western Germany this portion attains a thickness of 10,000 ft.
Except in Limburg, where, in the neighbourhood of Maastricht, the upper layers of the chalk are exposed and followed by Oligocene and Miocene beds, the whole of Holland is covered by recent deposits of considerable thickness, beneath which deep borings have revealed the existence of Pliocene beds similar to the " Crags " of East Anglia.
In the south of Holland the total thickness of the Pliocene series is only about 200 ft., and they are covered by about 100 ft.
Eastward and westward of Amsterdam, as well as southward, the Pliocene beds rise slowly to the surface, and gradually decrease in thickness.
After the piece has been reduced in thickness by its first passage or " pass " between the rolls, it may be given a second reduction and then a third and so on, either by bringing the two rolls nearer together, as in case of the plain rolls BB at the left in 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.
In the second period volcanic activity occurred at the bottom of the Pliocene sea, and the tufa, which extends over the whole Campagna to a thickness of 300 ft.
After being purchased at the auction sales they are washed, then stretched upon a hoop, when all blubber and unnecessary flesh is removed, and the pelt is reduced to an equal thickness, but not so thin as it is finally rendered.
Subsequently the hard top hairs are taken out as in the case of otters and beavers and the whole thoroughly cleaned in the revolving drums. The close underwool, which is of a slightly wavy nature and mostly of a pale drab colour, is then dyed by repeated applications of a rich dark brown colour, one coat after another, each being allowed to thoroughly dry before the next is put on, till the effect is almost a lustrous black on the top. The whole is again put through the cleaning process and evenly reduced in thickness by revolving emery wheels, and eventually finished off in the palest buff colour.
Sulphur is wrought in the district of Pinczow; the deposits, which contain 25% of sulphur, reach a thickness of 7 to 70 ft.
No other tool is so endurable, or gives such uniform thickness of wire.
These deposits attain their maximum thickness of 90 ft.
To take the simple case of the " wall " or flat plate considered by Fourier for the definition of thermal conductivity, suppose that a quantity of heat Q passes in the time T through an area A of a plate of conductivity k and thickness x, the sides of which are constantly maintained at temperatures B' and 8".
If the plate is thin, it is necessary to measure the thickness with great care, and it is necessary to assume that the temperatures of the surfaces are the same as those of the media with which they are in contact, since there is no room to insert thermometers in the plate itself.
The disks were 10 cms. in diam., and nearly 2 cms. thick, plated with copper to a thickness of 2 mm.
If the thickness of the glass is small compared with the diameter of the tube, say one-tenth, equation (1) may be applied with sufficient approximation, the area A being taken as the mean between the internal and external surfaces.
It is necessary that the thickness x should be approximately uniform.
The emissivity was reduced to one-quarter by lagging the bar like a steam-pipe to a thickness of i in.
It consists of a bridge of i i 1 arches, each 5 metres span, with piers of 2 metres thickness.
Here there are more, than 6o beds, of a total thickness of 150 to 200 ft.
The thickness of 80 beds amounts to 250 ft., and the total mass of coal is estimated at 45,400 million tons.
This deposit varies in thickness, as a rule, from 55 to 70 ft., at which depth it is underlain by a series of coarse and fine yellow quartz sands, with occasional pebbles, or even banks of gravel, while here and there thin beds of clay occur.
These sand-beds are sharply distinguished by their color from the overlying Nile deposit, and are of considerable thickness.
In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue, known as cambium; by the formation of a layer of cambium between the bundles (interfascicular cambium) a complete ring is formed, and a regular periodical increase in thickness results from it by the development of xylem on the inside and phloem on the outside.
The mineral occurs generally in lenticular deposits, which may reach a thickness of more than loo ft.; but it is mined only to a limited extent, most of the salt being obtained from brine springs and wells which derive their saline character from deposits of salts.
A bed of rock-salt in the Zechstein at Sperenberg near Berlin has been proved by boring to have a thickness of upwards of 4000 ft.
The workings in Great Britain represent the annual abstraction of rather more than a mass of rock equal to a foot in thickness spread over a square mile.
Secondary growth in thickness is effected by the tangential division of superficial cells.
The total thickness of both these groups of rock cannot be less than 30,000 ft., and, as most of them bear evidence of having been deposited in shallow water, they could only have been accumulated during a prolonged period of depression.
They have in some places a thickness of 7000 ft.
Red sandstones and conglomerates, probably of the same age, attain a thickness of several hundred feet at Gruinard Bay on the west coast of the county of Ross and Cromarty.
These plateaus are composed of nearly horizontal sheets of basalt - columnar, amorphous or amygdaloidal - which, in Ben More, in Mull, attain a thickness of more than 3000 ft.
Above the Boulder Clay are found sands and gravels, along with perched boulders which, by their source and position, indicate the direction and thickness of the ice that carried them.
Their features are generally fairly regular and often beautiful; eyes invariably black, and in some persons oblique; jaws not projecting, except in a few instances; lips of medium thickness; the noses are naturally long, well shaped and arched, but many are artificially flattened at the bridge in infancy.
Planks are allowed from a half to two-thirds of the above time, according to their thickness.
Soft clay was then carefully laid on to strengthen the mould, in considerable thickness, till the whole statue appeared like a shapeless mass of clay, round which iron hoops were bound to hold it all 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.
This distinction of thickness is of importance in its bearing on workshop practice.
Not only is more powerful machinery required for the latter, but in bending it allowance has to be made for the difference in radius of outer and inner layers, which increases with increase of thickness.
A thin sheet has for all practical purposes no thickness - that is, the geometrical pattern marked on it will develop the object required after it is bent.
But in any case the thickness must enter into the calculations, whereas in thin sheets no account is taken of thickness.
Only common geometrical problems are involved in the case of sheets of sensible thickness, and allowances are made for thickness.
But in those forms where curving must take place in different directions the layers or fibres of metal are made to glide over one another, extension taking place in some layers but not in others, and this goes on without producing much reduction in the thickness.
The result is that the object assumes a smooth concave and convex shape, without the thickness of the metal becoming reduced.
They consist of marine beds alternating with freshwater and littoral deposits, together with plant beds and coal-seams of considerable thickness.
The thickness of the delta deposit is unknown; 481 ft.
Ferguson has shown that the sediment is carried away from this area by the set of the currents; probably then it has remained free from sediment whilst the neighbouring sea bottom has gradually been filled up. If so, the thickness of the alluvium is at least 1800 ft., and may be much more.
The lower, with an estimated thickness of only 2000 ft., or slightly more, cover a large area - extending, with but little change of character, from the Sone valley in one direction to Cuddapah, and in a diverging line to near Bijapur - in each case a distance of over loo m.
The upper Vindhyans cover a much smaller area, but attain a thickness of about 12,000 ft.
The average thickness of the seams worked is from 12 to 18 ft., but occasionally a seam attains a great thickness - 20 to 80 ft.
Consequently, for a certain focal length, much deeper curves must be resorted to if the new glasses are to be employed; this means not only greater difficulties in workmanship, but also greater thickness of glass, which militates against the chance of obtaining large disks quite free from striae and perfect in their state of annealing.
This ratio will become more equal for larger sizes on account of the additional thickness of larger object-glasses and the consequent additional absorption of light in transmission.
By making the mirrors of silvered glass, one-fourth of their diameter in thickness, the Henrys have not only `.
Barnard's photographs of its structure leave little doubt on the matter; the numerous rifts and dark openings show that its thickness cannot be very great.
In its modern form the Leyden jar consists of a widemouthed bottle of thin English flint glass of uniform thickness p. 512.
Igneous rocks are not extensively developed; in Wales they form an important feature and occur in considerable thickness; they are represented by lavas of olivine-diabase and by contemporaneous tuffs which are traversed by later granite and quartz felsite.
Considerable variations occur in the thickness of Cambrian deposits, which may generally be explained by the greater rapidity of deposition in some areas than in others.
The effective radius, or radius of the pitch-circle of a circular pulley or drum, is equal to the real radius added to half the thickness of the connector.
Cavendish measured the capacity of disks and condensers of various forms, and proved that the capacity of a Leyden pane is proportional to the surface of the tinfoil and inversely as the thickness of the glass.
The cathodes are frequently of electro-deposited copper, deposited to a thickness of about 3 1 in.
The fibre is decidedly inferior to flax and hemp in strength and tenacity; and, owing to a peculiarity in its microscopic structure, by which the walls of the separate cells composing the fibre vary much in thickness at different points, the single strands of fibre are of unequal strength.
The doublings play a very important part in the appearance of the ultimate rove and yarn, for the chief reason for doubling threads or slivers is to minimize irregularities of thickness and of colour in the material.
Compared with the Gondwana coal of the peninsula of India the Tertiary coal seams of Assam are remarkable for their purity and their extraordinary thickness.
In the western and northern alpine part of Sweden, near the boundaries of Norway, the Silurian strata are covered by crystalline rocks, mica schists, quartzites, &c., of an enormous thickness, which have been brought into their present positions upon a thrust-plane.
They are generally of insignificant thickness.
The deposits are generally in pockets, and the thickness of the beds ranges from 100 to nearly 500 ft.
Between the folded marine beds of the Himalaya and the nearly horizontal strata of the peninsula lies the Indo-Gangetic plain, covered by an enormous thickness of alluvial and wind-blown deposits of recent date.
He also experimented on the effects of the thickness of the film, and came to the conclusion that the thinner a film is, the greater is its tension.
This result, however, was tested by Van der Mensbrugghe, who found that the tension is the same for the same liquid whatever be the thickness, as long as the film does not burst.
Since e is a line of insensible magnitude compared with the dimensions of the mass of liquid and the principal radii of curvature of its surface, the volume of the shell whose surface is S and thickness will be and that of the interior space will be V - SE.
If we suppose a normal v less than E to be drawn from the surface S into the liquid, we may divide the shell into elementary shells whose thickness is dv, in each of which the density and other properties of the liquid will be constant.
If we take the axis of z normal to either surface of the film, the radius of curvature of which we suppose to be very great compared with its thickness c, and if p is the density, and x the energy of unit of mass at depth z, then o- = f o dz, (16) and e = f a xpdz,.
If the thickness of the film is greater than 2E, there will be a stratum of thickness c-2E in the middle of the film, within which the values of p and x will be pc and In the two strata on either side of this the law, according to which p and x depend on the depth, will be the same as in a liquid mass of large dimensions.
On the hypothesis of uniform density we shall find that this is true for films whose thickness exceeds The symbol x is defined as the energy of unit of mass of the substance.
If the liquid forms a stratum of thickness c, then x = x' - 47rpo(o) +27rpo(z) +27rpo(Z - c).
Hence if il.(c) is positive, the tension and the thickness will increase together.
Now 2 7rmpi,t(c) represents the attraction between a particle m and the plane surface of an infinite mass of the liquid, when the distance of the particle outside the surface is c. Now, the force between the particle and the liquid is certainly, on the whole, attractive; but if between any two small values of c it should be repulsive, then for films whose thickness lies between these values the tension will increase as the thickness diminishes, but for all other cases the tension will diminish as the thickness diminishes.
If the density be a, the attraction between the whole of one side and a layer upon the other distant z from the plane and of thickness dz is 27r6 2 P(z)dz, reckoned per unit of area.
These rapidly descend in Newton's scale and at last disappear, showing that the thickness of the film is less than the tenth part of the length of a wave of light.
Suppose that the transition from o to s is made in two equal steps, the thickness of the intermediate layer of density la being large compared to the range of the molecular forces, but small in comparison with the radius of curvature.
When the liquid is in equilibrium it forms a thin film, the outer edge of which is all of the same thickness.
The thickness of the film of oil adequate to check the camphor movements can be determined with fair accuracy by depositing a weighed amount of oil (such as 8 mg.) upon the surface of water in a large bath.
Calculated as if the density were the same as in a normal state, the thickness of the film is found to be about two millionths of a millimetre.
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 endoderm is generally also an epithelium one cell in thickness, the cells being digestive, secretory and sometimes muscular.
As the juice exudes, more petals are pressed on to them with a cloth until a layer of sufficient thickness is obtained.
In the Branchiopoda the maxillary gland is lodged in the thickness of the shell-fold (when this is present), and, from this circumstance, it often receives the somewhat misleading name of " shell-gland."
The thickness of the ice does not exceed 3 or 4 ft.; but during the alternations of cold and warm weather, with strong gales, in winter, stacks of ice, 70 and 80 ft.
In the region of Adigrat the metamorphic rocks are invariably overlain by white and brown sandstones, unfossiliferous, and attaining a maximum thickness of moo feet.
The upper (Magdala group) contains much trachytic rock of considerable thickness, lying perfectly horizontally, and giving rise to a series of terraced ridges characteristic of central Abyssinia.
In order to obtain the cultivated bark as economically as possible, experiments were made which resulted in the discovery that, if the bark were removed from the trunks in alternate strips so as not to injure the cambium, or actively growing zone, a new layer of bark was formed in one year which was richer in quinine than the original bark and equal in thickness to that of two or three years' ordinary growth.
If the rust so covered up has not begun to pit the iron the chances are that it will do no harm; but, if it is already well developed and of some thickness, it will have enough oxidizing agents in its pores to develop more oxide, and to swell up and crack the paint.
Some architects depend solely upon partitions, and a building with a well-constructed iron frame should be safe if provided with brick partitions or if the exterior of the iron framework is covered with well-built masonry of sufficient thickness.
The great thickness of the Gangetic alluvium is shown by a borehole at Calcutta which was carried to a depth of about 460 f t.
The method consists in comparing the intensity after transmission through a layer of known thickness of the absorbent with the intensity of light from the same source which has not passed through the medium, k being thus obtained for various thicknesses and found to be constant.
In the case of solutions, if the absorption of the solvent is negligible, the effect of increasing the concentration of the absorbing solute is the same as that of increasing the thickness in the same ratio.
In a similar way the absorption of light in the coloured gas chlorine is found to be unaltered if the thickness is reduced by compression, because the density is increased in the same ratio that the thickness is reduced.
If white light is allowed to fall on some coloured solutions, the transmitted light is of one colour when the thickness of the solution is small, and of quite another colour if the thickness is great.
The seams are generally from one to five feet in thickness.
The corresponding intensity at the sun's surface is 4.62 X Io 4 as great, or 6.79 X Io 4 kilowatts per square metre = 7.88 X Io 4 horse-power per square yard - enough to melt a thickness of 13.3 metres (=39.6 ft.) of ice, or to vaporize 1.81 metres (=5.92 ft.) of water per minute.
Between ectoderm and endoderm is a supporting layer of structureless gelatinous substance termed mesogloea, secreted by the cell-layers of the body-wall; the mesogloea may be a very thin layer, or may reach a fair thickness, and then sometimes contains skeletal elements formed by cells which have migrated into it from the ectoderm.
These are overlain, perhaps unconformably, by a great thickness of lavas and volcanic breccias (Pniel volcanic series, Beer Vley and Zeekoe Baard amygdaloids), and these in turn by the quartzites, grits and shales of the Black Reef series.
The thickness of the rocks of the Cape System exceeds 5000 ft.
The greater part of the volcanic series is formed by lava streams of great thickness.
As the process continued the salt-saturated layer, incapable of further effective filtration, grew in thickness downwards, until in the process of time it filled the whole mass of sandstone.
Dams Any well-made earthen embankment of moderate height, and of such thickness and uniformity of construction as to ensure freedom from excessive percolation at any point, will in the course of time become almost impermeable to surface water standing against it; and when permeable rocks are covered with many feet of soil, the leakage through such soil from standing water newly placed above it generally diminishes rapidly, and in process of time often ceases entirely.
Thus the permeable vein grows vertically rather than horizontally, and ultimately assumes the form of a thin vertical sheet traversing the puddle wall, often diagonally in plan, and having a thickness which has varied in different cases from a few inches to a couple of feet or more, of almost clean sand rising to an observed height of 30 or 40 ft., and only arrested in its upward growth by the necessary lowering of the reservoir water to avoid serious danger.
Riveted sheets of steel have been occasionally used, and, where bedded in a sufficient thickness of concrete, with success.
A minimum thickness must safety be adopted to give substance to the upper part; and where the dam is not used as a weir it must necessarily rise several feet above the water, and may in either event have to carry a roadway.
The cost of this thickness being regarded as too great, it was abruptly reduced to 8 ft.
The thickness of sand is 3 ft.
This process may be repeated many times until the thickness of the fine sand is reduced to about 18 in., when the filter bed should be restored to its full thickness.
In the south-west salt is found in beds and dry incrustations, varying in thickness from a few inches to 2 ft.
The holder is made of sheet iron riveted together, the thickness depending upon the size of the holder.
At this time the Gulf of Bothnia must have suffered greater depression than the Baltic proper, for the deposits of that epoch show a thickness of 100 metres (328 ft.) near Hernosand, but of only 25 metres (82 ft.) in the neighbourhood of Gotland.
In the great basins and hollows from Rugen to the Gulfs of Bothnia and Finland the upper layers of water, from 30 to 70 metres (16 to 38 fathoms) in thickness, have almost the same salinity throughout.
Contorted stems, sometimes of considerable thickness, very hard, and covered with a grey cracked bark, rise out of the sand, bearing green plumes with small greyish leaves and pink fruit.
The black coral (Antipathes abies), formerly abundant in the Persian Gulf, and for which India is the chief market, has a wide distribution and grows to a considerable height and thickness in the tropical waters of the Great Barrier Reef of Australia.
From the relation of the thickness of the stem to its length it may be inferred that the shoots of Sphenophyllum derived support from adjoining plants.
They consist of slightly rounded domes or billowy snowfields of vast thickness.
These fossiliferous strata are developed in greatest thickness in the north-west peninsula.
This ice-cap had on the tableland a thickness of 2300 to 2600 ft.
Probably its original thickness Lough Neagh Tertiary Clays Eocene Basalt and Dolerite Cretaceous Trias, sometimes surmounted by Lower Jurassic Upper Carboniferous Carboniferous was not more than 150 ft., while now only from 40 to loo ft.
Towards the north-west, also, the Palaeozoic foundation falls beneath an increasing thickness of Cretaceous beds and lies buried far below the surface.
Almost the whole of this region is covered by a red soil, often of great thickness, which resembles and is often described as " clay," but is really decomposed rock, chiefly gneiss, reddened with oxidized magnetite.
True coal has also been obtained in the same district, the deposits varying from a third to half a metre in thickness.
The interior of the African portion of Gondwana Land was occupied by several large lakes in which an immense thickness - amounting to over 18,000 ft.
In order to isolate a polarized pencil of rays with a rhomb of Iceland spar, it is necessary to have a crystal of such a thickness that the emergent streams are separated, so that one may be stopped by a screen.
There are, however, certain crystals that with a moderate thickness give an emergent stream of light that is more or less completely polarized.
The crystalline plate shows no colour when it is very thin, and also when its thickness exceeds a moderate amount.
Thus a bar of glass of sufficient thickness, placed in the diagonal position between a crossed polarizer and analyser and bent in a plane perpendicular to that of vision, exhibits two sets of coloured bands separated by a neutral line, the double refraction being positive on the dilated and negative on the compressed side.
Arago pointed out, by supposing that in passing through the plate the plane of polarization of each monochromatic constituent is rotated by an amount dependent upon the frequency - an explanation that may be at once verified either by using monochromatic light or by analysing the light with a spectroscope, the spectrum in the latter case being traversed by one or more dark bands, according to the thickness of the plate, that pass along the spectrum from end to end as the analyser is rotated.
This is a plate made of two equal wedges of quartz, that can be moved over one another so as to vary its thickness, and are cut so that the faces of the plate are parallel to the optic axis, which in the first wedge is perpendicular and in the second is parallel to the refracting edge.
It is clear that direct transmission through the plate at a point where the thicknesses of the prisms are d 1 and d 2 will introduce a relative retardation of (µ,; -, u o) (d l - d2) between streams polarized in planes parallel and perpendicular to the edges of the prisms,, u o, and being the ordinary and the extraordinary refractive indices; and it is hence possible by an adjustment of the thickness to reduce elliptically polarized to plane polarization at an assigned point marked off by two parallel lines.
When the plates are of equal thickness, their combined effect is nil, but by adjusting the second, a rotation in the one or the other direction may be introduced, a scale attached to one prism and a vernier to the other giving the thickness of the resultant quartz plate.
At one end of the instrument is placed a polarizer and the biquartz, and at the other a Galilean telescope, that must be focused on the edge of biquartz, having in front of its object-glass the compensator and an analyser that is regulated for producing the sensitive tint, when the plates of the compensator have the same thickness.
The horizontal section (B) with equal clearness demonstrates the bee's ingenuity in economizing space, showing how the outer combs are used exclusively for stores, and, as such, may be built of varying thickness as more or less storage room is required.
Differences in view may, and do, exist regarding the thickness of the wood used in frame-making, but the outside measurement never varies.
For the microscopic observation it is the same as if a thin section of a thickness of 2 to 4 had been shown.
Objectives with definite undercorrection can however only produce really good images with glass covers of a specified thickness.
In systems with smaller apertures variations of the thickness of the glass cover are not so noticeable.
This expensive method was simplified in 1837 by Andrew Ross by making the upper and lower portion of the objective variable by means of a so-called correction-collar, and so giving the objective a corresponding under-correction according, to the thickness of the glass cover.
Especially powerful achromatic condensers are really only magnified microscope objectives, with the difference that they are not corrected for the thickness of the cover slip, but for the thickness of the glass on which the object is placed.
In order to determine the refractive index when the thickness of the crystal is known, or the thickness of the crystal when the index is known, a fine adjustment A makes it possible to measure exactly the changes in the length of the microscope.
The thickness of the cross wire may also occasion a fault.
This plate admits at the same time of a correct determination of the thickness of the cover glass, for which the best correction exists.
The endothecium varies in thickness, generally becoming thinner towards the part where the anther opens, and there disappears entirely.
Cork bricks made of compressed granulated cork are frequently used, a thickness of about 5 in.
The air spaces, two or three in number, are formed between two layers of tongued and grooved wood, and the total thickness of the insulation is about the same as when silicate cotton alone is used.
The material is either placed directly up to the skin of the vessel, and kept in place by a double lining of wood inside, in which case a thickness of about To in.
Given a certain allowable heat transmission, the principal points to be considered in connexion with insulation are, first cost, durability, weight and space occupied, the two last named being specially important factors on board ship. No exact rules can be laid down, as the conditions vary so greatly; and though experiments have been made to determine the actual heat conduction of various materials per unit of surface, thickness and temperature difference, the experience of actual practice is at present the only accepted guide.
In favourable cases remains of the cambium are found on the outer border of the wood, and phloem is also present in the normal position, though it does not seem to have attained any considerable thickness.
The tissue thus formed often attained a considerable thickness.
The development of periderm was a constant feature, and this tissue attained a great thickness, consisting chiefly of a phelloderm, produced on the inner side of the formative layer, and no doubt subserving a mechanical function.
The roots were at first like those of Marattiaceae but grew in thickness like the roots of Gymnosperms.
In the central parts of North America the lacustrine plant-bearing deposits are of enormous thickness, the Dakota series being followed by marine Cretaceous strata known as the Colorado and Montana groups, and these being succeeded conformably by a thousand feet or more of lacustrine shales, sandstones and coal-seams, belonging to the Laramie series.
Some clay rocks which have been laid down by water are very uniform through their whole thickness, and are called mud-stones.
It consists of parallel ridges and valleys developed by erosion on folded sandstones, shales and limestones, the valley quality predominating because the weak limestones were of great thickness.
The ice thickness distribution was inferred using remote sensing techniques.
The outer ward is nearly square, and its walls are nine feet in thickness and eighteen feet in height, surmounted by battlements.
Bags of this thickness are used regularly in high mountain bivouacs and could, in emergency, save life in this country.
The entire electromagnetic calorimeter at TESLA comprises a cylinder of length 5.5m, internal radius 1.9m, and annular thickness of 20cm.
High wing cantilever monoplane, tapering in plan form and thickness, built on a single box spar of corrugated light alloy sheet.
The wax thickness of 0.5mm provides sufficient strength to the finished casting to resist flexing whilst remaining unobtrusive in situ.
Dermagraft enables the damaged or destroyed dermis of a patient with a full thickness ulcer to be replaced.
This ambiguity can be resolved by transforming the measured color co-ordinates to compensate for the thickness of the papillary dermis.
Using 2mm thickness as a solid constructor makes the chassis durable and study.
Pure New Wool - Chunky A chunky thickness pure new wool ideal for knitting, dyeing and felting.
Carefully controlled electrolysis migrates metal atoms to the mandrel until the desired thickness is attained.
Assuming the corneal thickness = 1 unit, assess the width of the " aqueous gap " from corneal endothelium to iris.
Grade 2 Partial thickness skin loss involving epidermis, dermis or both.
Fittings shall be protected internally with a red powder epoxy resin electrostatically applied to a average thickness of 150 microns.
These are machined to a depth equal to half the specimen thickness and spaced equidistant from the specimen mid-length on opposing faces.
The thickness of the axial chromatin fibril is 6-10 nm.
These peptides will increase the skin's thickness, stimulate collagen fibroblasts, reduce wrinkles and generally improve the appearance of aging skin.
This a double thickness of heavy polar fleece rolled at the top, shown right.
The CryoSat program seeks to replace sporadic submarine missions by continual monitoring of the ice freeboard, from which thickness will be derived.
The wounds that are seen in plastic surgery are flaps, skin grafts and split thickness graft donor sites.
This mineral loaded product has a High Mass for minimum thickness which is equal to that of lead.
The original inglenook would have been considerably deeper than at present, built within the thickness of the property's main cross wall.
Performance Formica ® Compact grade is a decorative laminate with a thickness of at least 2mm.