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that state in any quantity, or with. phur in a large quantity of wate. out great difficulty, its characters This salt usually crystallizes into is can only be ascertained by examin. regular six-sided prisms, whose face ing its combinations with different are inclined to each other at anga bases. Some of the principal of these of 141° 39', 110° 45', and 107* $ will be here given. The hyposul. They refract doubly, and dissels phites are easily soluble in water, readily in water : at the temperatur and their solutions have either an of 37°, that liquid dissolves nearly intensely bitter, or intensely sweet own weight of them, and during the taste. When heated to a degree be. solution the thermometer sinks low redness, they are decomposed; 31o. At 50°, the specific gravity a 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 sols nitric acid, or a stream of chlorine tion contains 0.2081 of its on passed through their solutions, con- weight. These crystals are not verts 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, .....

.......................... 5.63 der, which is byposulphate of lead. 6 atoms water,

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

16.373 lution of any hyposulphite, precipi- Hyposulphite of potash is readily tate their respective metals in the prepared, either by precipitating the state of sulphurets. Nitrate of bis of lime by the carbonated alkali

, a muth when heated, undergoes the immediately decomposing hydrosul. same change ; while solutions of phuret or hydroguretted sulpburet 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 bitterneš, 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, beginning with that of lime, ed in precisely the same manner. which is the

most readily obtained in On cooling, it crystallizes in silk 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 naus sel, for ten or twelve days to the air,

When heated, it first under or by boiling, for a considerable goes the watery fusion, then dries time, the sulphite of lime with sul- into a white mass, and at length takes

seous.

e, burning with a vivid conflagra- combustior: wlien heated in the flame in and bright yellow flame. of a blow-pipe, it swells into a funHyposulphite of ammonia is not gous mass, by the escape of sulphur, sily procured in regular crystals. as borax does by that of water. s taste is excessively pungent, and Passing over the hyposulphites of cceeded by a disgusting bitterness. alumina and iron, the former of which "hen heated, it burns with a weak Mr Herschell endeavoured to insuime, and evaporates entirely. late, in various ways, without sucHyposulphite of barytes is a white cess, we come to the hyposulphite of illiant scaly powder, which is so- copper, which may be obtained by ble in dilute muriatic acid, but not digesting hyposulphite of lime on

2000 times its weight of water. carbonate of copper, or by mixing Then heated on a platina foil, it was sulphate of copper with hyposulphites irown into a singular agitation, and of lime, potash, &c. It is colourless, Pemed enveloped by a kind of fog and has an intensely sweet taste, aused by its own dust, thrown up in without any metallic flavour. It is a infinite number of minute explo- not decomposed by ammonia, nor ons. According to Mr Herschell's turned blue by an excess of that alnalysis, it is a compound of two a. kali, provided the air be excluded. oms acid plus one atom barytes. The copper in this salt is, therefore,

Hyposulphite of strontian crystal- in the state of protoxide. zes in flat rhombs, having the plane Hyposulphite of lead is a white ngles of their more extended sur. mealy powder, obtained by pouring aces, about 64° 45' and 115° 15'; but nitrate of lead into a neutral hypoheir solid form is that of an oblique sulphite, and when held long in the parallelopiped, whose sides are incli. mouth leaves an impression of sweetied to each other at angles of about ness. It requires for solution not 6° 30, 96° 45', and 97° 13. It is less than 3266 times its weight of loubly 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. Ac

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 formter, but is apparently not deliques. ed by adding nitrate 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

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

VOL. XII. PART 1.

Y

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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 ti combining with several of the other markable acid appear to be soluble. hyposulphites, and forming double Some curious experiments, former salts, which have some permanency. ly made by Sertürner, on the action Of these he has described the follow- of sulphuric acid on alcohol, here ing:

been repeated and confirmed by M.

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

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

correspond with those of the priso. Mr Herschell's experiments to They are transparent, and do 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 exhaust tisfactory results. It seems to fol. ed receiver along with sulphuric acid low from them, however, that hypo. Of this salt, when calcined, 100 perts 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 carbonat ous acid in a separate state, though of potash, and afterwards precipit: not 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 exactrecently 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 19 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 hyposul. phuric 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 watrated 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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ear in the Scientific Journals, it may Mr Smithson Tennant. This pore useful to collect and exhibit the tion was subjected to analysis by Dr esults, in a few instances.

Marcet; its specific gravity deterOf the water of the boiling spring mined to be 1.16507; and 500 grains 1 the harbour of Milto, Dr Thomo found to yield the following saline on analysed a specimen about a year contents : nd a half ago, and found its specific Common salt......... ....... 85.00 ravity to be 1.0331. Its saline con. Muriate of magnesia.............. 10.08 Lituents, in 500 grains of this water, Sulphate of soda.......... 40.26 letermined according to the me. hod described in the “ Annals of

185.34 Philosophy,” xiv. 27. are as follow : Common sa!t,......

........................20.924. From which it follows, that the waMuriate of lime,.............

.................... 3.505 ters of this lake contain a greater Sulphate of soda.............. 0.684 quantity of salt than any other mi

neral waters hitherto examined,

25.113 those of the Dead Sea excepted. So that it contains about one half The specific gravity of the water of per cent. more of salt than sea-water the Dead Sea, as determined by difdoes.

ferent chemists, varies a little. KlaMr Cooper examined a specimen of proth found it 1.245; Gay-Lussac, mineral water from the coast of Sus- 1.2283 ; and Dr Marcet, 1.211. sex between Newhaven and Rotting. But this difference is nothing comdean. It flows from a bed of chalk, pared to the discordance which preand its temperature is uniformly 600 vails as to the chemical constituents as it issues from the earth. Its speci. of the water itself, and which shows fic gravity is 1.076; so that it is con- how small progress has been made siderably heavier than the boiling in the art of analysing mineral waspring in the island of Milto. It is ters, and how little confidence can slightly acidulous, and has the taste be reposed, on such a subject, even of iron. Mr Cooper detected the in the most accurate of our experifollowing substances in it: oxide of menters. It is therefore of the ut. iron, alumina, muriátic acid, sul- most consequence that the succes. phuric acid, lime, carbonic acid, and sive steps of every analysis, and the soda.

method employed in calculating the We are indebted to Dr Marcet for respective proportions of each conan extensive set of experiments on stituent, should be carefully recordsea water, collected from different ed. Attention to this will always seas, and from different depths of render such experiments important; the same sea. Among others we while those who merely set down the find an analysis of the water of the results of their experiments furnish Lake Ourmia, in Persia, situated at us with no means of detecting their no great distance from the region of errors, and may rest assured that, Mount Ararat. A small quantity hereafter, when the mode of analysis of the water from this lake was sent has become more perfect than at by the late Mr Browne, the traveller, present, their conclusions will be of (of whose murder by Persian ban- no value whatever. In confirmation ditti, the reader will find an interest. of these remarks, and to point out ing and affecting account in the Tra- more forcibly the necessity of what vels of Sir Robert Ker Porter,) to we recommend, we shall here give the saline contents extracted from Sea, according to Marcet, Kler100 grains of water of the Dead roth, and Gay-Lussac.

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TAINS

Klaproth's salts were only dried at In this survey the accessible posithe temperature of boiling water, tions are determined with a sufficiezt which accounts for the much greater degree of accuracy, from the resoweight of his salts; but how are we lution of triangles, of which all the to reconcile the great discordance angles were observed; but inacces. between Marcet and Gay-Lussac in sible places could not of course be the weights of common salt and so correctly determined, as but two muriate of magnesia?

angles could be taken. In the in

stance, therefore, of the more eleheight or THE HIMALAYA MOUN- vated peaks of the Himalaya, the

distances were deduced from more

than one triangle, and the mean of Geometrical measurements, by the different results taken. Hence the persons engaged in geographical cases are not numerous where discresurveys at the foot of this stupend- pancies appeared amounting to more ous range, leave it no longer doubt. than 100 fathoms in distance, or 100 ful that the elevation of the moun- feet in height. Being satisfied, thee, tains which divide India from Tartary that the distances might be relied on, surpasses considerably that of the Captain Webb proceeded to calcu. Cordilleras of the Andes, formerly es- late the heights of the several peaks teemed the highest points on the sur- observed by him in the snowy range. face of the globe. In the 12th vo- The largest set of observations was lume of the Asiatic Researches ap- made at Calinath, an elevated stapeared a dissertation by H. T. Cole- tion, of which the height geometribrooke, Esq., in which he examines cally determined is 6417 feet above the information then existing (in the level of the sea, and barometri1814) and supports the general con- cally 6388 feet above the level of clusion already stated. Since that Calcutta. Four of these peaks, and time the inquiry has been farther among them the highest of the whole

, pursued, chiefly by Captain Webb, are distinctly visible at Casipur, and employed on a survey of the pro- were then observed. This station is in vince of Kemaon, recently ceded to the plain of Rohilkhund, and about the British by the Nepalese. A list 650 feet above the level of the sea. of the elevated peaks of the Hima. Every observation was repeated with laya mountains measured by him has the telescope reversed ; and a mean appeared in various publications, of the angles as read off on both sides and, as far as it goes, agrees with the of zero assumed. It was also ascer. ampler information contained in a tained that the telescope described memoir of his survey officially fur. true vertical angles, by bringing the nished by him.

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