SUL

SUL

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this gas, without agitation or extraordinarypreflure, abforbs, according to Prieltiey, b about44. times its bulk, or -jVo of its weight; andaccording to Thomfon, at 6i° Fahr. 33 timesits bulk, or -f-iyW’ of its weight; but if water befaturated with this gas, by means of a Woulfe’sapparatus, the bottles of which are furroundedwith ice, it will be found to have taken up, ac-cording to Vauquelin , c about T 'oV of its weight.The fpecific gravity of this liquid acid is ftatedby Berthollet at 1.04, and by Vauquelin at-1.02'j by Thomfon at 1.05 at 68°.

Oxygen gas appears to have no a£Hon on ful-phurous acid gas, when both the ingredients aredry; but if to a mixture of one part of the for-mer and two of the latter, there be added a verylittle water, a fudden diminution of bulk willat firft take place, owing to the abforption ofpart of the acid gas by the water; after whicha further gradual abforption happens, in confe-quence of an actual combination going on be-tween the two gafl'es, by which fulphuric acidis formed and part of the oxygen gas difappears.It is afferted by Fourcroy, that if a mixture ofoxygen and fulphurous acid gaffes are pafledthrough a red hot tube, fulphuric acid is formedby their combination : in this cafe, iiowever, itis probable that the gaffes were previoufly fa-turated with water; for it is perfedtly wellafcertained, that during the diftillation at ahigh red heat of calcined fuiphat of iron, there■comes over, befides fulphuric acid, a mixtureof fulphurous acid and oxygen gas, which maybe readily feparated from each other by meansof a dilute alkaline folution, which detains theformer, but allows the latter to pafs throughunaltered.

Oxymuriatic acid gas is readily decompofedby fulphurous acid ; the veflel becomes filledwith white vapours, and a mixture of fulphuricand muriatic acids is the refult.

Hydrogen gas and fulphurous acid exercifemo aftion on each other at the common tem-perature, but if a mixture of three parts, byhulk, of the former, and one of the latter, are■made to pafs through a red hot glafs tube, thefulphurous .acid is totally decompoled, and theprodu&s are fulphur, water, and fometimes alittle fulphuretted hydrogen.

Phofphorus, even when ftrongly heated in ajrlafs tube, appears to have no athion on ful-phurous acid gas. Phofphuretted hydrogen, onthe contrary, even at the common temperature,readily decompofes this acid ; the mixture lofesjts ltate of elaliic fluidity, a white vapour makes

* Experiin. methodized, vol. ii. p. 311.

its appearance, and the Tides of the veflel arelined with a mixture of fulphur and phofphorus.Sulphuretted hydrogen has a fimilar effedl tophofphuretted hydrogen, and fulphur is preci-pitated from the decompofition both of the acidand of the inflammable gas.

Charcoal, at the common temperature, im-bibes a confiderable quantity of fulphurous acidgas, but appears to produce no material changeupon it: at a red heat, however, the gas is de-compofed, fulphur is depofited, and fulphurettedhydrogen is produced; the hydrogen, doubtlefs,originating from the water either of the acid gasor of the charcoal.

With camphor, fulphurous acid combinesreadily, and the refult is a liquid, the propertiesof which have been but little inveftigated : thiscompound, when dropped into water, depofitsagain the camphor, which appears to have un-dergone fcarcely any alteration.

Sulphuric acid, efpecially at a low tempera-ture, abforbs a large proportion of fulphurousacid gas: the combination foon becomes folid,and in this ftate it has but little odour; but if aportion be laid on a piece of glafs and expofedto the air, it prefently refolves into a liquid, atthe fame time diiengaging, with a very vifibleeflervefcence, the greateft part of the fulphur-ous gas. Strong and colourlefs nitric acid, bybeing impregnated with fulphurous acid gas,acquires a deep orange tinge, and nitrous gas isdifengaged; the fulphurous being at the fametime converted into iulphuric acid.

Water, when faturated with fulphurous gas,forms the liquid fulphurous acid : it is belt pre-pared in a Woulfe’s apparatus, with two ormore bottles, into the firft of which fhould beput a little water, to take up the fulphuricacid with which the gas is generally more orlefs mixed, while the purified fulphurousacid is abforbed by the water in the fecondand fucceeding bottles. This liquid acidabforbs oxygen from the air, and is graduallyconverted into fulphuric acid. But if a little ofit is confined in a glafs tube, hermetically fealedand expofed to the common heat of a fand bathfor a few weeks, the infide of the tube will beobferved to be lined by degrees with minutecryftals : after a time the depofition of cryftalswill ceafe : if then the end of the tube bebroken off' under mercury, this latter fluid willrife in the tube, (hewing that a portion of theair has dilappeared, and the refidue, on exami-nation, will be found to be wholly deprived ofoxygen : the liquid which was pure fulphurous

* Ar. n. At Chim. vel. xxiv. p, *37.

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