AFFINITIES OF COMPRESSED CASES. 371 



of nitrogen) ; and an acid which reddened litmus paper. Mr. 

 Accum was prefent at this experiment, and from his opinion, 

 as well as from fucceeding experiments, I have reafon to think 

 that this acid is the nitric. 



Experiment II. 



As a difference of arrangement in the order of the gafes Exp. 2. The 

 tends confiderably to vary (he refult, I repeated the former^^ g U f * 

 experiment (having firft poured a little lime-water into the 

 receiver) by injecting firft the oxigen, about Jhree pints, then 

 equal quantities of hidrogen and nitrogen. Much of this gas 

 efcaped, owing to the imperfection of the inftrument; but 

 upon the affufion of the nitrogen, the white vapours again 

 appeared in the receiver ; water feemed likewife to be 

 formed ; and fome yellow particles were feen floating upon 

 the lime-water. Thefe particles probably arofe from the re- 

 finous fubflance, ufed in fattening on the cap of the receiver, 

 being diflblved by the nitrous gas formed during condenfation. 



I would juft obferve, that the magnet feemed to be affecled 

 during this experiment; but as there is iron ufed in the ma- 

 chine, this may be otherwife accounted for. 



Experiment III. 



Two pints , of Carbonic acid, and two of hidrogen, were Exp. 3. Carbo- 

 fubjeaed to condenfation. The refult was, a watery vapour, ™&* ^water 

 and a gas of rather ofFenfive fmeil. and a changed 



gas. 

 Experiment IV. 



Trying to inflame phofphorus by the condenfation of at- Exp. 4. Phof- 

 mofpheVic air, the bottom of the machine (where it had been £°™ j? con * 

 repaired) burft out with an explofion. This happened when 

 I had immerfed the apparatus in water to difcover where the 

 air efcaped. The receiver was full of the fumes of the phof- 

 phorus, which was itfelf difperfed in the veffel of water. 

 I afterwards repeated this experiment with the more perfect 

 apparatus, but I could not inflame the phofphorus, and the 

 fumes which arofe at firft foon difappeared. There was juft 

 enough acid (probably phofphoric) formed on the in fide of 

 the receiver to tinge litmus. 



B b 2 Experiment 



