4^4 On phofphorated Hydrogtn Gas. 



at the fame time to make the union as complete as poflible. I then unftopped the de- 

 canter, and inverted it in a fmall tub, full of newly diftilled water, to afcertain whether it 

 would be entirely filled with this water, by the mere preflure of the air, and that I might 

 alfo by this means be enabled to judge whether the whole of the gas had become liquefied. 



I accordingly faw that a portion of the water in the tub was fuddenly prefled into the 

 decanter, but not fo much as to fill it entirely, which fliewed that fome of the gas ftlll 

 remained uncombined with the water. I_next made trial of the abforbed gas by palTing a 

 few bubbles through the liquid, which took fire by contaft of the external air, and thus 

 proved that the phofphorated hydrogen gas had not been at all decompofed either by the 

 agitation, or by its contaft with the diftilled water ; whereas it fpeedily lofes its high de- 

 gree of combuftibility, when collected in veflels filled with undiftilled water, or with 

 water that had been diftilled for a length of time. This efFeft I attribute to the quantity 

 of air held in folution by common water, the oxygen of which coming in contact with a 

 portion of phofphorus feparates it from the hydrogen, by converting it into phofphoreus 

 oxide, which being perfedtly infoluble, is depofited on the inCde of the glafs, without 

 affording any perceptible combuftion in this kind of oxidation ; becaufe the oxygen of the 

 atmofphcric air, which partakes of the liquidity of water, being thus deprived of a great 

 part of the caloric and light combined with it, during its aerial aggregation, cannot pro- 

 duce both thofe efiedls in a perceptible manner, when it pafles from one combination to 

 another in this ftate of liquid aggregation. 



Having again fliaken the decanter, after clofing its mouth, I fucceeded by means of the 

 fmall quantity of water which had entered, and of which I kept an accurate account in 

 obtaining the abforptlon of the reft of the gas ; for on opening the veflel again, it foon 

 became entirely filled with water. Hence I may venture to afiirm, from the diverCfied 

 trials, as well as from feveral others which I (hall pafs over, that water which has been de- 

 prived of its air by diftillation, is capable of diflblving and liquifying at the ordinary tem- 

 perature, rather lefs than one fourth of its bulk of phofphorated hydrogen gas, and that by 

 this proportion it Is completely faturated. 



This folution, prepared according to the above dire£lions, and preferved from the cen- 

 tal of air, has always exhibited the following properties : its colour is nearly fimilar to 

 that of roll brimftone, though in general pale. Its fmell is ftrong and difagreeable, and 

 its tafte extremely bitter, thougli infipid and naufeous. 



On examining this folution in the dark, it did not appear in the leaft luminous, a proof 

 that the phofphorus had intimately combined with the hydrogen, 



When diftilled in a fmall retort with the pneumato-chemical apparatus, a little below 

 the temperature of boiling water, and particularly if fubmitted when recently prepared, it 

 aflforded a confiderable quantity of -phofphorated hydrogen gas, equally pure and combuf- 

 tible as that obtained by heating cauftic alkalies, or quick lime with phofphorus, and the 

 addition of a fmall quantity of water. What remained in the retort after the difengage- 



xaent 



