Prisms Sentence Examples

Prisms deflect rays of light towards their bases.

The acid is thus obtained in colourless rhombic prisms of the composition C 6 H 8 0 7 +H 2 0.

In this way the principal features of the phenomenon are accounted for, and Schuster has shown further how to extend the results to spectra having their origin in prisms instead of gratings.

It forms large rhombic prisms, has a somewhat saline taste and is easily soluble in water.

It crystallizes from alcohol in prisms, which are sparingly soluble in water.

On evaporating this solution the hydrated salt CoI 2.6H 2 0 is obtained in hexagonal prisms. It behaves in an analogous manner to CoBr 2.6H 2 0 on heating.

These three adjustments having been made, the prisms P3 and P4 are removed and replaced by another prism in which the silvering is arranged as in fig.

It forms quadratic prisms, having a violet reflex and insoluble in boiling hydrochloric acid.

Potassium ruthenate, K2Ru04 H20, obtained by fusion of the metal with caustic potash and nitre, crystallizes in prisms which become covered with a black deposit on exposure to moist air.

A solution of the pure salt yields fine prisms of the composition Na2Sn03+10H20, which effloresce in the air.

When slowly crystallized it forms large monoclinic prisms which are readily soluble in water but difficultly soluble in alcohol.

By heating the nitrate it is obtained as hemimorphous pyramids belonging to the hexagonal system; and by heating the chloride in a current of steam as hexagonal prisms. It is insoluble in water; it dissolves readily in all aqueous acids, with formation of salts.

The salt crystallizes out on cooling with 7 molecules of water, forming colourless orthorhombic prisms, usually small and needle-shaped.

It crystallizes in quadratic prisms and has a bitter taste.

He also made great use of the simple dark chamber for his optical experiments with prisms, &c. Joseph Priestley (1772) mentions the application of the solar microscope, both to the small and portable and the large camera obscura.

It crystallizes from water (in which it is very soluble) in monoclinic prisms which approximate in composition to Sr(N03)2.4H20 or Sr(N03)2.5H20.

Prisms are of great value in cases of double vision due to a slight tendency to squinting, caused by weakness or over-action of the muscular apparatus of the eyeball.

These prisms may be combined with concave lenses, which correct the myopia, or, since a concave lens may be considered as composed of two prisms united at their apices, the same effect may be obtained by making the distance between the centres of the concave lenses greater than that between the centres of the pupils.

After experiments in the Zeiss works, the erecting of Porro's prisms simultaneously permitted a convenient adaptation to the eye-distance of the observer.

The hydrated acid crystallizes in prisms which effloresce in air, and are readily soluble in water.

The iodaurates, correspond to the chlorand bromaurates; the potassium salt, KAuI 4, forms highly lustrous, intensely black, four-sided prisms.

It forms colourless, monoclinic prisms, which turn brown on exposure to air.

The normal nitrate, Bi(N03)3.5H20, is obtained in large transparent asymmetric prisms by evaporating a solution of the metal in nitric acid.

The microscopes adjoining 82 read the position and declination circles; for, by an ingenious arrangement of prisms and screens, the images of both circles can be read by each single microscope as shown in fig.

In the last the field is full of false light, and it is not possible to give sufficiently minute and steady separation to the images; and there are of necessity a collimator, two prisms of total reflection, and a small telescope through which the rays must pass; consequently there is great loss of light.

He fell upon a most ingenious plan of doubling the amount of double refraction of a prism by using two prisms of rock-crystal, so cut out of the solid as to give each the same quantity of double refraction, and yet to double the quantity in the effect produced.

It forms colourless, very hygroscopic prisms, which attack glass, slowly at ordinary temperatures, more rapidly when heated (Ber., 1909, 4 2, p. 49 2).

It crystallizes in short hard prisms, which are readily soluble in water but insoluble in alcohol.

Caesium nitrate, CsNO 3, is obtained by dissolving the carbonate in nitric acid, and crystallizes in glittering prisms, which melt readily, and on heating evolve oxygen and leave a residue of caesium nitrite.

It forms monoclinic prisms (with IoH 2 O) which are permanent in air.

Calcium nitrate, Ca(N0,)2.4H20, is a highly deliquescent salt, crystallizing in monoclinic prisms, and occurring in various natural waters, as an efflorescence in limestone caverns, and in the neighbourhood of decaying nitrogenous organic matter.

It crystallizes in colourless prisms, possessing a saline taste; it sublimes on heating and is easily soluble in water.

It crystallizes in small prisms, having a sharp saline taste, and is exceedingly soluble in water.

It crystallizes in large transparent prisms, which melt on heating and decompose, leaving a residue of metaphosphoric acid, (HP03).

It crystallizes in quadratic prisms.

Before 1868 Maxwell conducted the experiment by sending light from the illuminated cross-wires of an observing telescope forward through the object-glass, and through a train of prisms, and then reflecting it back along the same path; any influence of convection would conspire in altering both refractions, but yet no displacement of the image depending on the earth's motion was detected.

Pyrazine, C4H4N2, crystallizes from water in prisms, which have a heliotrope odour.

Newton also made use of the method of crossed prisms, which has been found of great use in studying dispersion.

It crystallizes from water in colourless rhombic prisms, containing four molecules of water of crystallization, and possesses a very acid reaction.

It crystallizes in dark red monoclinic prisms which are readily soluble in water.

It crystallizes in dark red prisms which are readily soluble in water; it is a valuable reagent for the detection of sulphur, this element when in the form of an alkaline sulphide giving a characteristic purple blue coloration with the nitroprusside.

The best kind of charcoal is that of close-grained pine or alder; it is cut in short prisms, having a flat smooth surface at right angles to the rings of growth.

The nitrate, Cr(NO 3) 3.9H 2 0, crystallizes in purple prisms and results on dissolving the hydroxide in nitric acid, its solution turns green on boiling.

The zone of the external surface of the mantle within the edge secretes a layer formed of prisms of calcite; the rest of the epithelium from this zone to the apex secretes the inner layer of the shell, composed of successive laminae; this is the nacreous layer, and in certain species has a commercial value as nacre or mother-of-pearl.

The humerus lacks a foramen at the lower end; and the molar teeth, as explained and illustrated in the article Vole, consist of two longitudinal rows of triangular alternating vertical prisms, and may be either rootless or rooted.

A prism or a train of prisms. These are employed in instruments of small power, especially when luminosity is a consideration; but their advantage in this respect is to a great extent lost, when, in order to secure increased resolving power, the size of the prisms, or their number, is unduly increased.

In the case of prisms the resolving power ist (dµ/dX), where t is the effective thickness of the medium traversed by the ray.

When compound prisms are used in which, 1 Monthly Notices R.A.S.

Liquid prisms, however, suffer from the fact that any change of temperature involves a change in the refractive index of the prism.

The power may be increased, but with a diminution of intensity, by using a train of prisms. Steinheil made an instrument of four prisms, each of which had, however, to be set in the position of minimum deviation by trial.

In Browning's form the setting is automatic. The dispersion may be further increased by causing the rays to pass more than once through the prism or prisms. Thus, by means of a system of reflecting prisms, Hilger passed the dispersed rays six times through one prism, and, by similar means, Browning passed the rays first through the upper part of a train and then back through the lower part.

Compound prisms are also employed.

Rutherfurd devised one made of flint glass with two crown glass compensating prisms; whilst Thallon employed a hollow prism containing carbon bisulphide also compensated by flint glass prisms. In direct vision spectroscopes the refracting prisms and slit are in the observing telescope.

The prisms are necessarily compound, and usually consist of flint glass with compensating prisms of crown.

In all cases where compound prisms are used, the angles must be accurately calculated.

Amici in 1860 devised such an instrument; an improved form by Jannsen was made up of two flint and three crown prisms, and in Browning's form there are three flint and four crown.

Strychnine crystallizes from alcohol in colourless prisms, which are practically insoluble in water, and with difficulty soluble in the common organic solvents.

Thomas Young explained the parhelic circle (P) as due to reflection from the vertical faces of the long prisms and the bases of the short ones.

Reflection from an excess of horizontal prisms gives rise to a vertical circle passing through the sun.

As the sun rises, the rays enter the prisms more and more obliquely, and the angle of minimum deviation increases; but since the emergent ray makes the same angle with the refracting edge as the incident ray, it follows that the parhelia will remain on the parhelic circle, while receding from the inner halo.

The "arcs of Lowitz" (L) are probably due to small oscillations of the vertical prisms.

The rays, rendered parallel by the collimator objective, meet a plane mirror (f) of silvered glass, which reflects them to the prisms (g, g').

These, as shown in the figure, are composed of a variable number of vertical triangular prisms, in contact with one another by two (or one) of their angles.

On the number and relations of these prisms the voles, which form an exceedingly large group, ranging all over Europe and Asia north of (and inclusive of) the Himalaya, and North America, are divided into genera and subgenera.

The molar teeth have respectively 5, 5 and 6 prisms above, and 9, 5 and 3 below.

In the upper jaw the first molar has 5, the second 4 and the third 4 prisms, of which the last is irregular and sometimes divided into two, making 5.

In the lower jaw the first molar has 7 prisms, of which the 3 anterior are generally not fully separated from one another, the second 5 and the third 3.

It forms resplendent monoclinic prisms, soluble in water.

Thallous sulphate, T1 2 SO 4, forms rhombic prisms, soluble in water, which melt at a red heat with decomposition, sulphur dioxide being evolved.

Thallous nitrate, T1NO 31 is obtained as white, rhombic prisms by crystallizing a solution of the metal, oxide, carbonate, &c., in nitric acid.

It crystallizes in dark purple-red prisms, isomorphous with potassium perchlorate.

The observer's eye is applied to the small telescope E, which (by means of prisms numbered I, 2, 3, 4) views the vernier attached to the cross-head simultaneously with the hour circle attached to the upper end of the polar axis.

An excellent feature is the short distance between the eye-piece and the declination axis, so that 1 In the bent telescope refracting prisms are employed at the corners to change the direction of the rays.

Evaporation of a solution at ordinary temperatures gives colourless monoclinic prisms of Th(SO 4) 2.9H 2 O, which is isomorphous with uranium sulphate, U(S04)2.9H20.

Rubidium nitrate, RbNO 3, obtained by the action of nitric acid on the carbonate, crystallizes in needles or prisms and when strongly heated is transformed into a mixture of nitrite and oxide.

A crystalline form was obtained by Debray as olive-green prisms by igniting a mixture of sodium tungstate and carbonate in a current of hydrochloric acid gas, and by Nordenskjold by heating hydrated tungstic acid with borax.

The salt forms large monoclinic prisms; molecules containing 25 and 21 H 2 O separate from solutions crystallized at higher temperatures.

On boiling gelatinous silica with ammonium polytungstate and evaporating with the occasional addition of ammonia, ammonium silicodecitungstate is obtained as short rhombic prisms. On adding silver nitrate and decomposing the precipitated silver salt with hydrochloric acid, a solution is obtained which on evaporation in a vacuum gives the free acid as a glassy mass.

If this be dissolved in water and the solution concentrated, some silicic acid separates and the filtrate deposits triclinic prisms of tungstosilicic acid.

They are square, oblong or circular in section, and the interior is fitted with horizontal or inclined plates or prisms, which regulate the fall of the ore.

In the Gerstenhoffer and Hasenclever-Helbig furnaces the fall is retarded by prisms and inclined plates.

A saturated solution of the hydroxide deposits on cooling a hydrated form Ba(OH) 2.8H 2 0, as colourless quadratic prisms, which on exposure to air lose seven molecules of water of crystallization.

It crystallizes in monoclinic prisms of composition Ba(103) 2 H 2 O, and is only very sparingly soluble in cold water.

Boiling alcohol extracts from the root a neutral substance in the form of crystalline prisms, which crystallize in scales from boiling water.

By rapid evaporation of its solution it may be obtained in small prisms. The pentaflhoride SbF 5 results when metantimonic acid is dissolved in hydrofluoric acid, and the solution is evaporated.

Soc. Morphine, or morphia, crystallizes in prisms with one molecule of water; it is soluble in woo parts of cold water and in 160 of boiling water, and may be crystallized from alcohol; it is almost insoluble in ether and chloroform.

It crystallizes in shining rhombic prisms from its aqueous solution and as delicate needles from alcohol.

It crystallizes in needles or prisms and volatilizes when heated, giving a pale yellow vapour.

Faces of prisms other than m are also small and of exceptional occurrence.

The sodium salt, Na 4 P 2 0 6.10H 2 O, forms monoclinic prisms and in solution is strongly alkaline; the acid salt, Na3HP206.9H20, forms monoclinic tablets.

It crystallizes in white or pale fawn-coloured acicular prisms or silky needles, and is soluble in alcohol and ether, and in loo parts of cold and 3 of boiling water; it is without odour and has an astringent and an acid taste and reaction.

Diphenylfulven, from benzophenone and cyclo-pentadiene, crystallizes in deep red prisms. Dimethylfulven is an orangecoloured oil which oxidizes rapidly on exposure.

It crystallizes in colourless prisms and is optically active.

It is known that he purchased prisms and lenses on two or three several occasions, and also chemicals and a furnace, apparently for chemical experiments; but he also employed part of his time on the theory of fluxions and other branches of pure mathematics.

It appears that Newton made the mistake of supposing that all prisms would give a spectrum of exactly the same length; the objections of his opponents led him to measure carefully the lengths of spectra formed by prisms of different angles and of different refractive indices; and it seems strange that he was not led thereby to the discovery of the different dispersive powers of different refractive substances.

It forms small hard prisms which become red on exposure to air containing ammonia, owing to the formation of murexide (ammonium purpurate),C $ 11 4 (NH 4)N 5 0 6.

Ferrous fluoride, FeF21 is obtained as colourless prisms (with 8H2O) by dissolving iron in hydrofluoric acid, or as anhydrous colourless rhombic prisms by heating iron or ferric chloride in dry hydrofluoric acid gas.

Arsenides, Arsenites, &c. - Several iron arsenides occur as minerals; lolingite, FeAs 2, forms silvery rhombic prisms; mispickel or arsenical pyrites, Fe2AsS2, is an important commercial source of arsenic. A basic ferric arsenite, 4Fe2O3 As2O3.5H 2 O, is obtained as a flocculent brown precipitate by adding an arsenite to ferric acetate, or by shaking freshly prepared ferric hydrate with a solution of arsenious oxide.

Realgar occurs native in orange prisms of specific gravity 3.5; it is prepared artificially by fusing together arsenic and sulphur, but the resulting products vary somewhat in composition; it is readily fusible and sublimes unchanged, and burns on heating in a current of oxygen, forming arsenic trioxide and sulphur dioxide.

Orpiment (auri pigmentum) occurs native in pale yellow rhombic prisms, and can be obtained in the amorphous form by passing a current of sulphuretted hydrogen gas through a solution of arsenious oxide or an arsenite, previously acidified with dilute hydrochloric acid.

Since the two circular streams have different speeds, Fresnel argued that it would be possible to separate them by oblique refraction, and though the divergence is small, since the difference of their refractive indices in the case of quartz is only about o 00007, he succeeded by a suitable arrangement of alternately rightand left-handed prisms of quartz in resolving a plane-polarized stream into two distinct circularly polarized streams. A similar arrangement was used by Ernst v.

Wollaston, by blocking off one of the streams with a screen, sufficient lateral separation being obtained by combining two equal crystalline prisms cut differently with respect to the optic axis - an arrangement that achromatizes more or less completely the pencil that is allowed to pass.

In a second type, called Nicol's prisms, one stream is removed by total reflection.

This is made by fixing a thin crystalline plate between two glass prisms turned in opposite directions by a cement of the same refractive index as the glass.

This refractive index should be equal to the greatest index of the plate, and with a biaxal plate the mean axis of optical symmetry should be parallel to its faces and in the normal section of the prisms, while with an uniaxal plate the optic axis should be in a plane perpendicular to this normal section.

These prisms have the advantage of economy of material and of a greater field than the ordinary Nicol's prism, but a difficulty seems to be experienced in finding a suitable permanent cement.

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.

It crystallizes in colourless prisms with one molecule of water, which redden on exposure.

He realized that the division of the cones of rays by prisms could only be satisfactorily performed if the prism was placed in the position of the exit pupil of the objective or in the position of the real image of this exit pupil.

He employed a Nachet combination of prisms and placed the dividing prism at the spot where a special reversing system formed a real image of the exit pupil of the objective.

The system of Porro prisms employed affords a convenient method of adapting the ends of the eyepieces to the interpupillary distance.

Such a combination of prisms was used by Wenham, who placed it directly behind the last objective lens.

As a rule this arrangement of prisms can be exchanged for the Wenham stereoscopic reflection-prisms.

The surfaces of the dividing prisms must be very exact, so that no deterioration of the image may arise from them.

By the supplementary use of one of Wenham's prisms every ray is analysed into a more powerful refracted and a weaker reflected one.

Nicols's, Glan-Thomson prisms or similar polarization apparatus are used as polarizers and analysers.

It crystallizes in yellow rhombic prisms, and is readily soluble in water, the solution having a bitter taste and an alkaline reaction.

It forms large triclinic prisms of specific gravity 2.6-2.7, which are moderately soluble in cold water and readily soluble in hot water.

Examination of fixation using vertical prisms is useful in diagnosing amblyopia in the absence of strabismus.

All Hilkinson Binoculars have fully multi-coated optics and have either BK-7 or BAK-4 prisms.

All models have the benefit of multi-coated optics and phase coated prisms for extra brightness and clarity.

In addition to a common White system three quartz prisms are set up near the front mirror to work as reflectors.

The buttons carry light collecting prisms attached to optical fibers in a 10m cable that directly feeds a spectrograph on the dome floor.

Suppose now the solar spectrogram to be viewed in the focus of Or, and the converging rays to be reflected by the prisms Pr and P, i till an image is formed in the focus of the eyepiece at the point where the axis of the eyepiece intersects From Zeitschr.

If the stellar spectrograph is viewed in the focus of 0 2 and the converging rays are reflected by the prism P2 to P4, no image would be seen in the eyepiece, for the rays would pass out directly through the parallel glass plate which is formed by the cementing together of the prisms P 3 and P 4.

This has the effect of forming the image of the latter farther from the observer's eye, and so it becomes necessary to turn the handle of the rack-pinion V in such a way as to move the prisms P3 and P4 nearer to P2 till the lines of the stellar spectrograph are again sharply in focus.

The best crystals are the brilliant, blackish-brown prisms with terminal pyramidal planes (fig.) from the Restormel iron mines at Lostwithiel, and the Botallack mine at St Just in Cornwall.

Again, to obviate the necessity for excessive convergence of the eyes so common in hypermetropia, the centre of the pupil should be placed outside the centre of the corrective convex lenses; these will then act as prisms with their bases inwards.

Micros, 18 53, p. 236; 1854, pp. 18-24) published an arrangement of prisms, which, however, imparted a pseudomorphous impression if image-forming oculars were not used, and in 1854 a second system (fig.

Prism Type- Roof prisms are the easiest to waterproof (important if you are outdoors in all types of weather and fog).

Porro prisms are the least expensive to manufacture.

It forms green prisms which are readily soluble in water.

Of the aromatic compounds azo-benzene is bright orange-red, and a-azonaphthalene forms red needles or small steel-blue prisms. The azogroup, however, has little or no colouring effect when present in a ring system, such as in cinnolene, phthalazine and tolazone.

They all crystallize in the monoclinic system, often, however, in forms closely resembling those of the rhombohedral or orthorhombic systems. Crystals have usually the form of hexagonal or rhomb-shaped scales, plates or prisms, with plane FIG.

These often have the form of prisms of calcite surrounded by a cuti cular meshwork; the whole is nourished and kept alive by processes, which in Crania are branched; these perforate the shell and permit the access of the coelomic fluid throughout its substance.

It crystallizes in prisms with four molecules of water; when.

The whole island is strewn with natural basaltic prisms, some of great size; and of this material, brought by boats or rafts from a distance of 30 m.

Let AoBo be a plane wave-surface of the light before it falls upon the prisms, AB the corresponding wave-surface for a particular part of the spectrum after the light has passed the prisms, or after it has passed the eye-piece of the observing telescope.

It is obtained as fine lemon yellow deliquescent prisms by evaporating a solution of any of the oxides in nitric acid.

The haematoidin pigment may vary in colour from yellowish or orange-red to a ruby-red, and forms granular masses, rhombic prisms or acicular crystals.

The price, however, rapidly increases with the total bulk of perfect glass required in one piece, so that large disks of glass suitable for telescope objectives of wide aperture, or blocks for large prisms, become exceedingly costly.

Similarly the first moment of a solid figure may be regarded as obtained by dividing the figure into elementary prisms by two sets of parallel planes, and concentrating the volume of each prism at its centre.

This also holds for higher moments, provided that the edges of the elementary strips or prisms are parallel to the line or plane with regard to which the moments are taken.

It forms glancing prisms of neutral reaction slightly soluble in water.

By dissolving red lead, Pb304, in glacial acetic acid and crystallizing the filtrate, colourless monoclinic prisms of lead tetracetate, Pb(C2H302)4, are obtained.

He would have been more at home in a state of things which did not demand from its leading statesman great popular power; he had none of those " isms " and " prisms of fancy " which stood in such good stead some of his rivals.