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CHAPTER III.

VIEW OF IMPROVEMENTS IN SCIENCE DURING THE YEAR.

Light.- Heat.-Hyposulphurous acid and its compounds.-Discovery of

Hyposulphuric Acid.--Experiments of Sertürner, Vogel, and Gay Lussac, on the action of sulphuric acid on alcohol. --Mineral waters.-Mea. surement of the height of the Himalaya Mountains.Curve of permanent congelation.

LIGHT AND HEAT.

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position of his needles; for, if they

had been placed nearly in the magOn the interesting subjects of Light netic meridian, a certain temperaand Heat, no great quantity of ad- ture preserved for a certain time ditional information was brought may be conceived to be capable of into view during the course of this inducing permanent magnetism. year. It will be recollected, that, The most remarkable paper on some years ago, Morichini bad

per. the subject of heat is an early proformed a set of experiments,' by duction of Professor Leslie, “On which he professed to have discover- Heat and Climate,” which had been ed that steel wire, when exposed for read at two meetings of the Royal a certain time to the violet rays of Society as far back as the year 1793, the sun, becomes magnetised. These but was first published in the “ Anexperiments have been repeated nals of Philosophy" for July 1819. by various philosophers, general. The novelty of the views developed in ly without success; though there this ingenious performance, its total are some who affirm that they have deviation from the opinions generalverified Morichini's discovery. The ly received at the time, and the disreality of this power of the violet regard of authority evinced by the rays was, therefore, very generally author, appear to have startled the called in question, till it was an. Committee of the Royal Society, and nounced in the Bibliothéque Univer- prevented them from inserting it in selle, that the late Professor Playfair their Transactions. As far as Mr had witnessed a successful experi- Leslie was concerned, this was perment of this kind. Since the time haps fortunate. It induced him to of this announcement, various other re-consider the subject, and probapersons, and, among the rest, M. bly led to most of the investigations Dhombres Firmas, have tried this afterwards given to the world in his experiment, and have uniformly fail. “ Inquiry into the Nature and Proed. The success of Morichini's ex- pagation of Heat ;" a work which perinent must, therefore, have, in has deservedly raised the author to all probability, been owing to the the highest rank in science as a pro

found thinker and original discoverer. plates; and when this number is Into the peculiar doctrines develop. very great, as in Deluc's column, the ed in this ingenious paper, it would calorific effects become evanescent. be obviously superfluous to enter at The caloric is evolved, by the inpresent; but there is one operation crease of surface; and he has shown which we beg leave to notice, be that it may be very intense, even cause we consider it inaccurate in when only a single pair of plates is point of fact. Professor Leslie says, used. Upon this principle, he conthat, on descending into the deepest structed a battery, which produced mines, no sensible increase of tem- intense ignition without any electriperature is ever observed. Now, cal phenomena. the fact is, that, in the copper mines of Cornwall, it is no uncommon thing HYPOSULPHUROUS ACID AND ITS to find the air hot enough to raise

COMBINATIONS. the thermometer to 100°; and that, in the salt mines of Cheshire, the But one of the most important in. miners work without their clothes, vestigations connected with experi. and rather complain of heat than mental chemistry, which this year cold. Dr Thomson supposed the produced, is that of Mr Herschell, temperature of the air in the salt on the hyposulphurous acid and its mine at Nantwich to range between compounds. An accident first led 80° and 90°; and it will be seen him to the prosecution of the inquiry, from a table published by Mr Bald, which has conducted to some inte. that the air and the water at the resting results. Having set aside, for bottom of the deep coal mines in a few days, a solution of hydrogu. Durham, Cumberland, Northumberretted sulphuret of lime, he was land, and Stafford, are from 19° to struck by observing a bitterness in 19° higher than at the surface of the the liquid when almost wholly deearth. Whether we attempt to ex. composed and colourless, similar to plain this difference by the theory that of magnesia, the presence of of subterranean or central fire, or which he at first suspected, but was by any other hypothesis, the fact it- soon undeceived.

The liquid had self is undoubted ; and we are rather lost its property of precipitating surprised that a philosopher so re- iron or copper from their solutions markable as well for the accuracy of in the state of sulphurets, though it his information, as for the delicacy still gave a copious precipitate to the of his experiments, and the origina- carbonated alkalies, and of course lity of his views, should have fallen retained lime in some state of union into such an error.

with an acid, which could not be

either the sulphuric or sulphurous, GALVANISM.

neither of these forming double

salts with lime. The inquiry now Dr Hare, of America, has publish- became interesting, and was pured a theory of galvanism, differing sued with great success by the inconsiderably from all those hitherto genious chemist we have just namstarted. According to him the gal. ed. vanic fluid is a compound of electri. The hyposulphurous acid not becity and caloric. The electricity is ing capable of a separate existence, increased by the number of pairs of or at least not being procurable in

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that state in any quantity, or with. phur in a large quantity of water. out great difficulty, its characters 'This salt usually crystallizes into ircan only be ascertained by examin. regular six-sided prisms, whose faces ing its combinations with different are inclined to each other at angles bases. Some of the principal of these of 1+1° 39', 110° 45', and 107° 36'. will be here given. The hyposul. They retract doubly, and dissolve phites are easily soluble in water, readily in water : at the temperature and their solutions have either an of 37°, that liquid dissolves nearly its intensely bitter, or intensely sweet own weight of them, and during the taste. When heated to a degree be. solution the thermometer sinks to low redness, they are decomposed; 31o. At 50°, the specific gravity of and while sulphur separates, a sul- a saturated solution is 1.300; and phite, or in some cases a sulphuret when the temperature is 60°, and the of the base remains. The action of specific gravity 1.114371, the solunitric acid, or a stream of chlorine tion contains 0.2081 of its own passed through their solutions, con- weight. These crystals are not alverts them into sulphates. The hy- tered by exposure to air, unless it be posulphites and their solutions are very dry. From Mr Herschell's exdecomposed by all other acids, ex- periments, this salt appears to be cept the carbonic, especially when composed of heated with them. They precipitate 2 atoms hyposulphurous acid, 6.000 lead from its solutions in white pow. 1 atom lime, ....

3.625 der, which is hyposulphate of lead. 6 atoms water,

6.750 Oxi-nitrate of silver, and nitrate of mercury, dropped into a dilute so

16.375 lution of any hyposulphite, precipi- Hyposulphite of potash is readily tate their respective metals in the prepared, either by precipitating that state of sulphurets. Nitrate of bis- of lime by the carbonated alkali, or muth when heated, undergoes the immediately decomposing hydrosul. same change ; while solutions of phuret or hydroguretted sulphuret manganese, iron, zinc, copper, tin, of potash by sulphurous acid, and suffer no such precipitation. But evaporating to a pellicle. It then one of the most remarkable proper. crystallizes into a confused mass of ties of the hyposulphites is that spiculæ. It has a penetrating taste which their solutions possess of dis- like nitre, succeeded by bitterness, solving muriate of silver, and re. and deliquesces readily when extaining it in considerable quantity in posed to the air. When heated, it permanent solution.

dries down to a white mass, then We shall now proceed to give a takes fire, and burns like a piece of condensed description of the salts tinder. which Mr Herschell succeeded in Hyposulphite of soda may be formforming, begioning with that of lime, ed in precisely the same manner. which is the most readily obtained in On cooling, it crystallizes in silky a state of purity.

tufts radiating from centres, which Hyposulphite of lime may be form. at length extend through the whole ed by exposing the hydroguretted liquid, and become almost solid. Its sulphuret of that alkali in a flat ves- taste is intensely bitter and nau• sel, for ten or twelve days to the air, seous. When heated, it first under. or by boiling, for a considerable goes the watery fusion, then dries time, the sulphite of lime with sulinto a white mass, and at length takes fire, burning with a vivid conflagra- combustior: when heated in the flame tion and bright yellow flame. of a blow-pipe, it swells into a fun

Hyposulphite of ammonia is not gous mass, by the escape of sulphur, easily procured in regular crystals. as borax does by that of water. Its taste is excessively pungent, and Passing over the hyposulphites of succeeded by a disgusting bitterness. alumina and iron, the former of which When heated, it burns with a weak Mr Herschell endeavoured to insu. flame, and evaporates entirely. late, in various ways, without suc

Hyposulphite of barytes is a white cess, we come to the hyposulphite of brilliant scaly powder, which is so- copper, which may be obtained by luble in dilute muriatic acid, but not digesting hyposulphite of lime on in 2000 times its weight of water. carbonate of copper, or by mixing When heated on a platina foil, it was sulphate of copper with hyposulphites thrown into a singular agitation, and of lime, potash, &c. It is colourless, seemed enveloped by a kind of fog and has an intensely sweet taste, caused by its own dust, thrown up in without any metallic flavour. It is an infinite number of minute explo- not decomposed by ammonia, nor sions. According to Mr Herschell's turned blue by an excess of that alanalysis, it is a compound of two a. kali, provided the air be excluded. toms acid plus one atom barytes. The copper in this salt is, therefore,

Hyposulphite of strontian crystal- in the state of protoxide. lizes in flat rhombs, having the plane Hyposulphite of lead is a white angles of their more extended sur mealy powder, obtained by pouring faces, about 64° 45' and 115° 15'; but nitrate of lead into a neutral hypotheir solid form is that of an oblique sulphite, and when held long in the parallelopiped, whose sides are incli. mouth leaves an impression of sweetned to each other at angles of about It requires for solution not 76° 30, 96° 45', and 97° 13. It is less than 3266 times its weight of doubly refractive, and soluble in water. When heated even below about four times its weight of water 212° it turns black; and when the at the temperature of 45°, while it temperature is raised, takes fire, and, dissolves in 1.75 times its weight of becoming red hot, burns with a weak boiling water. Its taste is excessive- flame. If it be now removed from ly bitter. It is insoluble in alcohol; the fire, the ignition and combustion but readily dissolves muriate of sil- may be maintained for any length of ver, while alcohol precipitates the so- time, by cautiously adding small lution in the state of a sweet syrup. quantities of the substance. Aca

Hyposulphite of magnesia is easily cording to the analysis of Mr Herformed by boiling a solution of sul- schell, this salt is composed of two phite of magnesia with flowers of sul- atoms acid plus one atom protoxide phur. It readily crystallizes, is in- of lead. tensely bitter, dissolves easily in wa- Hyposulphite of silver may be form. ter, but is apparently not deliques. ed by adding bitrate of silver to a cent. When laid on a hot iron, it diluted solution of any hyposulphite. burns with a weak blue flame; but is It has an exceedingly sweet taste *. incapable per se of maintaining the In a short time it is decomposed, and

ness.

• The sudden production of intense sweetness, by mixing two such disgustingly bitter liquids as nitrate of silver and hyposulphite of soda is very iking, and proves how little we know of the manner in which bodies affect the organs of taste.

VOL. XII. PART 1.

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sulphuret of silver precipitated. Mr phurous acid escapes, and nothing Herschell has shown that the hypo- remains but sulphuric acid. All the sulphite of silver has the property of salts formed with bases by this recombining with several of the other markable acid appear to be soluble. hyposulphites, and forming double Some curious experiments, formersalts, which have some permanency. ly made by Sertürner, on the action Of these he has described the follow- of sulphuric acid on alcohol, have ing:

been repeated and confirmed by M.

Vogel of Munich, and especially by
Hyposulphite of potash and silver. M. Gay-Lussac, who prepared sul-

of soda and silver. phovinate of barytes in a state of
of ammonia and silver. purity, and subjected the acid to ana-
of lime and silver. lysis. It crystallizes in fine rhom-
of strontian and silver. boidal prisms, terminated by four-
of lead and silver. sided pyramids, the faces of which

correspond with those of the prism. Mr Herschell's experiments to They are transparent, and do not procure the hyposulphite of mercury alter in the open air, but become do not appear to have led to very sa. opaque when kept under an exhausttisfactory results. It seems to fol. ed receiver along with sulphuric acid. low from them, however, that hypo. Of this salt, when calcined, 100 parts sulphurous acid is capable of com- dried in the air lost 45.07 parts, and bining with the peroxide, but not furnished 54.93 parts of sulphate of with the protoxide of mercury. His barytes. The same quantity of salt, trials also to procure hyposulphur. calcined with chlorate and carbonate ous acid in a separate state, though of potash, and afterwards precipitanot completely successful, seem not ted by muriate of barytes, yielded entirely to preclude the hope of here. 111.47 parts of sulphate of barytes, after accomplishing it.

or nearly double what was obtained

in the first experiment. Thus, it apHyposulphuric acid has been only pears, that the acid possesses exact. recently discovered by Gay-Lussac ly the constituents and the capacity and Welter, who obtained it by pass- of saturation of hyposulphuric acid, ing a current of sulphurous gas and that the vegetable matter which through water in which the black it holds in combination produces no oxide of manganese was suspend. alteration in these particulars. This ed. Sulphates and hyposulphates curious subject requires much fuller of manganese were formed. These investigation. salts were decomposed by means Four new alkaline substances have of carbonate of barytes, and no- been discovered and described by the thing remained but hyposulphate of French chemists, to which they have barytes, which was crystallized, re- given the names of morphine, strychdissolved in water, and the barytes nine, brucine, delphine, and picroprecipitated by the cautious addition toxine. They have been found in the of sulphuric acid. From these ex. seeds, bark, or fruit of vegetables. periments, it appears that hyposulphuric acid is a compound of one

MINERAL WATERS. atom of sulphuric, plus one atom of sulphurous acid. It may be concen- Analyses of certain mineral wa. trated to a certain point; but if the ters, in different parts of the world, concentration be farther urged, sul. having appeared in the course of the

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