Ohfcrvat'mis mid IiiilnBioilS rt/pefthig the Cowpofitkn <if IVr.f,;-. 353 



t)scn fliewnthat the water enters into the compofition of carbonic acid; and until that is 

 proved, it is warrantable to fuppofe that the water ferves to difengage the carbonic acid, by 

 attrafting and uniting with the baryt ; efpecially as tliis acid gaz may be wholly fcparated 

 from other fubftances without the intermediation of water, and as it can be compounded 

 by uniting the driefl: carbon to the dried oxygen gaz. Further, although carbonic acid 

 gaz be very apt to contain water, it may be obtained in fo dry a ftate as not to indicate 

 nioiilure to the moft delicate lefts. 



The next fa£l affords a fort of analytical proof; v/hich is the exiflence of water in air 

 or gaz in general, as fliewn by muriate of lime, acetite of pot-afli, fulphuric aeid, quicklime, 

 pot-afh, &c. But the abforption of water by thefe fubilances only fhews that it may be 

 fufpended or diflblved in gazes ; but not that it enters into their compofition. Gaz may 

 be obtained or rendered quite free from water, as juft faid ; and as the compounds by the 

 combination of the gazes with various different fubftances are quite different from the com- 

 pounds by the combination of water with the fame various different fubftances, there does 

 not appear to be in this cafe any admifhble evidence of water being an elfential conftituent 

 fubftance in the compofition of gazes. 



The experiments of fcparating oxygen and nitrogen gaz from water by boiling, and by 

 cxpoling it in vacuo and applying caloric, only fliew how n'luch more tenacioufly, and in 

 how much greater quantity, thefe gazes are contained in water than is commonly fuppofed ; 

 for however long a given quantity of water yielded gaz, fo that there feemed no limit to the 

 quantity, the water which afl'orded it was flill very confiderably greater than the weight or 

 quantity of gaz. 



With refpedt to the other opinion, that hydrogen and oxygen gaz are compounded of a 

 peculiar bafis and caloric, and that water is compounded of thefe two bafes — i . It has been 

 (hewn by an experiment, the accuracy of which is not qucflionabre, that when thefe two 

 gazes produce water by combuflion, the amount of the weight of the water is exactly the 

 weight of the gazes confumed, and that no ponderable matter but water is produced vi'heii 

 nothing but the bafes of thefe two gazes unite ; but that when other fubftances, fuch as 

 nitrous acid and carbonic acid, were produced, as well as water, then nitrogen and carbon 

 were prcfent. 2. It has been ftiewn, that when oxygen in a concrete ftate, as in metallic 

 oxides, unites to the hydrogen of hydrogen gaz, the water thus compounded is equal in 

 weight to that of the hydrogen gaz confumed, and the deficient weight of the oxide. 3. It 

 appears that when hydrogen in a concrete ftate, as in alcohol, is united to the oxygen of 

 oxygen gaz, the water compounded is equal in weight to the weight of the alcohol ancf 

 oxygen gaz confumed, provided the addition be made of the carbonic acid alfo producej 

 by the carbon of the alcohol. The carbon of alcohol can be fliewn by analyfis ; and its 

 exiftcnce in carbonic acid can be fliewn both by analyfis and fynthefis. 4. When water is , 

 applied to certain fubftances, notliing but hydrogen gaz is obtained, and new compounds, 

 the conftituent parts of which arc oxygen and the fubftance applied ; for thefe new com- 

 pounds have the fame properties as the compounds of the fame fubftances fo applied to 

 water, and of the oxygen of oxygen gaz. And in thefe cafes the additional weight derived 

 from the water, together with the weight of the hydrogen gaz feparated from the water, is 

 equal to the water deftroyed. 5. It has been rendered at leaft very probable, that when 

 oxygen and Iiydrogcn arc rendered into the gaz ftate, they abforb or unite with a 

 Vol. I — Novtur.tR 1797. Z z ■ large 



