cadet's fuming liquor. 7 



in different veffels. The heavieft, as being the mod ufeful to Examination of 

 be known, was firft examined. At the commencement he the heavieft « 

 was affecled by the thick vapours which it difperfes through 

 the air, and by its extremely penetrating and horribly fetid 

 odour. Its aclion on the animal economy is To powerful, that It powerfully af- 

 he found it impofiible to devote more than one hour in a day ma i ec0 nomy." 

 to his enquiries, and he was more than once tempted to aban- 

 don them. He was in the fame Hate as if he had taken a 

 ftrong medicine, and experienced ftupefying effects ; againft 

 which he employed fulphurated hidrogen diffolved in water, 

 with fuccefs. 



As he had but a fmall quantity of the liquor at his difpofal, Order of the in.- 

 and it was of importance that his attempts fhould not be fruit- ve 1 6 atl0n - 

 lefs, he regulated the order of his enquiries in this manner : 

 He firft determined the caufe of the odour which it fpreads 

 through the air ; then he fought for that of the thick vapours 

 which it produces, and afterwards that of its fpontaneous in- 

 flammation ; and he made ufe of the determination of thefe 

 three points to difcover the fourth, and moft important, the 

 constituent principles of the fubftance. 



The odour could only proceed from the fubftance itfelf, Caufe of the 

 or elfe from an elaftic fluid which it might hold in folution, ° 

 and which the author fuppofed to be arfeniated hidrogen. He 

 therefore diddled, with great care, a certain quantity of the 

 liquor in a fmall glafs retort, to which were adapted a re- 

 ceiver and a tube for collecting the gafes. He obtained no- The liquor was 



thing but the air of the veflels ; the liquor was entirely vola- "" cl ?, anged b * 

 ■11 i rr i • i • • , i difhllation. 



ulized, and palled into the receiver without having undergone 



any alteration, except that its colour was not quite fo deep. 

 Hence the odour of the arfenical liquor is owing to its pro- 

 perty of being volatilized, and, probably, diffolved in the air. 



The caufe of its vapours could only be owing to an ab- Its vapour is oc- 



forntion of oxigen, or to an ablorption of the water diffolved c f ( " 10ned b y ^ n 

 • . • i • i r a- a i /• • m, ■ abforption of ox- 



m the air, or to both thele effects at the lame time. I he air igen and water. 



of a flalk, into which Cit. Thenard had poured a few drops, 

 immediately loft its tranfparency, and, in a fhort time, be- 

 came incapable of fupporting the combuftion of a taper. A 

 veffel of the fame fize, filled with carbonic acid, offered the 

 fame phenomena, but in a lefs diftinct manner. To guard 

 againft the contact of the air, he had been careful to fufpend 

 a very thin tube, containing the liquor, to the cork of theflafk, 



