COMPOSITION OF WATER, &C. 2^5 



tfie different liquors between the plates of the pile; all of 

 whicli bad a feniible effect upon the gafes, both upon the 

 quantity produced, and their kind; the calcinable wires when 

 long producing the moft inflammable kinds, and the lefs calci- 

 nable metals the more of the oxigen kind, and the longer the 

 wires the more in volume were the gafes. 



Mr. Northmore, in your Journal, endeavours to prove the Remarks on 

 formation of the nitric acid from the compreffion of gafes. — Mr. North- _ 

 Upon inveftigalion, his experiments will, I think, be found ments. 

 very vague and inconclufive : that gafes from adtive compref- 

 fion will produce both heat and water, has been long known. 

 The firft experiment was in condenfing hidrogen, oxigen and 

 nitrogen gafes, two pints of each. He fays they produced 

 " white floating vapours, probably (he gafeous oxide;" but 

 in experiment the feventh, he obferves, •• the hydrogen pro- 

 duced white clouds at firft, qucere ammonia," So without any 

 chemical examination ol' (hefe white clouds, they are at firft 

 fuppofed to be the gafeous oxide, and afterwards auimonia, 

 juft according as his theory didates to him. In the fifth ex- 

 periment, he fays, " and the refult was only a fmell of ga- 

 feous oxide of nitrogen, a few yellowith fumes." Here then 

 the gafeous oxide produces a yellowifli colour, though in the 

 firft experiment it was a white colour. 



The acid produced was, from the fame vague opinion, fup- 

 pofed to be the nitric; but this he endeavours to examine in 

 the next experiment ; firft by a good teft, in expofing it to 

 lime water; and he fays, " Some yellow particles were feen 

 floating upon the lime water; thefe particles probably arofe 

 from the reftnous fubftance ufed in faftening on the cap of the 

 receiver being diflblved by the nitrous gas formed during con- 

 denfation. Here then was the lime water affeded. , I fay 

 with confidence, thefe floccuH in the lime water were from 

 the carbonic acid produced, and why they appeared yellow 

 was from their being feen through the gafes, being clouded 

 with an orange colour, which, as he obferves, they put on 

 when they were condenfed. 



That acids are neceflary in forming oxigen gas, I hope ap- 

 pears very clear from my experiments; therefore when it forms 

 combuftion with inflammable bodies, it is rational to fuppole 

 that an acid will appear upon its decompofition. If the com- 

 l^uftion is aflive, as in the French experiments in condenfing 



oxigeft 



