3 5+ Ittdunms refptEi'mg the Compojil'wn of Waier, 



large quantity of caloric, or of both calivic and lifilit. I might add, that hefidcs the pofi- 

 tivc evidence juft ftatcd, there does not appear to be ar.y evidence to contravene the con- 

 dufion that water is compounled of hydrogen and oxygen ; and that thefe gazes arc com- 

 pounded of a peculiar bafis, called hydrogen and oxygen, united to caloric : for it would 

 be eafy to fliew, but it would be digrcffing too far, that the remaining partizans of the 

 phlogillic fecTl have advanced erroneous evidence in fome cafes, and in others have negleClcd 

 the confideralion of oppofing but well authenticated evidence. 



In the experiments contained in this paper no fupport can be found for the former 

 opinion concerning water, and hydrogen and oxygen gaz ; but they confirm the latter 

 opinion. For, i.the combuflion of thefe gazes, rendered perfeilly dry, ^afforded water, 

 p. 303, Exp. IV. 2. The evidence from the procefs above defcribed is peculiar; for no 

 one other procefs affords oxygen and hydrogen gaz from water. In all other procefles for 

 decompounding water, either the decompounding concrete fubtlance receives fomething 

 from the water applied, and at the fame time hydrogen gaz is produced ; as in the inftance 

 of paffnig water through a red-hot iron tube : or the decompounding concrete fubflance 

 receives fomething from the water; and this compound unites to that in water, which pro- 

 duces hydrogen gaz with caloric ; as in the inftance of applying water to red-hot carbon : 

 or two decompounding fubilances being applied, each of them receives a different thing 

 from the water, namely, hydrogen and oxygen. Hence, by the procefs above defcribed, the 

 objeclion is removed, that the hydrogen gaz might be feparated from the decompounding 

 fubftance itfelf, by water taking its place. 3. The produdlion of hydrogen and oxygen gaz, 

 pnd the produftion of water by the combuftion of them, in the above procefs, afford an 

 additional evidence of the decompofition and compofition of water, and of hydrogen and 

 oxvgen gaz ; as the mode of their produ£tion by this procefs is perfe(flly conDftent with 

 the rationale of their produdion in all other cafes. 



Thus it appears that the grandell difeovery ever made in chemical philofophy, by an 

 jUuftrious member of this Society, in 178J, has been confirmed by a number of fubfequent 

 experiments. The body of evidence is indeed fo numerous, and of fuch a nature, that, in 

 the minds of thofe who underftand its import, and who rely on the accuracy of the weights 

 and meafures employed, it produces as much conviction concerning the compofition of 

 water as can be obtained by the evidence of almoft any other cafe of compofition. I mufl, 

 however, beg leave to protcft againft thofe able philofophers, who have maintained, that the 

 compofition of water, and fcveral gazes, has received full and complete demonflration ; by 

 fuch unwarrantable pretenfions their adverfaries have obtained over them fome advantages. 

 For in the chain of caufes and effeifls there are fome links which cannot be explained by 

 the direcl evidence of fenfe ; and there, in fo far as we admit hypothefes, although con- 

 fiflent with the phenomena, wc m^y be faid to quit day-light, notwithllanding we at tlie 

 next ftep emerge into light derived from the perceptions of fenfe. For inftance, if I com- 

 bine a certain known weight of hydrogen and oxygen by combudion of their gazes, and 

 produce water equal in weight to that of thefe gazes ; and if 1 again refolve this water, by 

 means of the electric fire, or red-hot iron, into the original quantity of hydrogen gaz and 

 oxvgen, I cannot give the full and complete demonftration of tlie compofition of water 

 and thefe gazes : for, as I proceed in the interpretation, I at length come to dcmonftrate 

 the mode of agency of the particles of the hydrogen and oxygen gaz on one another 



when 



