Difficulties otteiid'inj^ the E'peiment. 24 J 



muriatic acid, which contains a very large proportion of water, adords hydrogen gaz only, 

 the oxygen being abforbed by the muriatic acid, and becoming oxy-muriatic acid. 



From much experience I can fafely affirm, that it is fcarcely poffibk for the ftudent, or 

 even the proficient, to inftitute the above experiment with fuccefs from the explanation 

 publifhed. Hence, during the fix years which have elapfed fince its publication, no con- 

 firmation has been publilhed except the experiment repeated by Mr. Cuthbertfon, for my 

 fatisfadtion, as related in my work on the chemical nomenclature ; but I have heard of 

 many perfons, and fome of whom were experienced electricians and chenufls, who made 

 the attempt. 



Since Mr. Cuthbertfon came to refide in London, I have learned from him the circum- 

 ftances requifite to the fuccefs of the experiment ; and I have received from him alfo very 

 great affiftance in continuing a procefs with the objedls I had in view, the tedioufnefs and 

 even ditBculties of which can only be conceived by thofe who have hizn. engaged in the 

 fame purfuit. 



I am very fenfible that it would be unneceflary for me to explain the importance of a pro- 

 cefs which may at laft afford demonftration of the compofition of water, by the fullefl and 

 unequivocal evidence of its analyfis and fynthefis ; a demonftration which no other Cnglc 

 procefs but the prefent promifes to afford. 



I propofe therefore in this paper : 



1. To give fuch a defcription of the experiment of rendering water into gaz by eleftric 

 difcharges, as fhall enable any perfon who is verfed in pneumati? chemiftry, and acquainted 

 with the theory and pra£lice of eleclricity, to repeat it with fuccefs. By this defcription, 

 alfo, I apprehend I fhall make known more generally the very elegant, and frequently moft 

 fatisfaftory, mode of decompounding and compounding bodies, by means of the fire of the 

 eleflric difcharge. 



a. It is propofed to relate the additional evidence which I have already obtained from this 

 procefs, concerning the compofition of water. For although it feems moft probable that 

 water is really decompounded in Mr. Van Trooftwyk's experiment, it man; be confeffed 

 that it does not make appear a fingle unequivocal and decifive property of hydrogen and 

 oxygen in the gaz produced. The difappearance of this gaz by combuftion, or in fome other 

 way, inftantly on paffmg through it an eleflric fpark, it is true, is a property known only to 

 belong to the mixnire of oxygen and hydrogen gaz ; but it is well afcertained, that things 

 of totally different fpecies may agree in one or more properties. And there is at leaft a poffi- 

 bility, that ele£tric difcharges may produce various other kinds of gazes in water, befide 

 hydrogen and oxygen from decompounded water; and which may have the property of 

 inftantly difappeariiig on paffing throu'gh them an ele£lric fpark. 



3, I (liall attempt to rcfolve the phenomena of the procefs into a general law of the a6\ion 

 of fire, or of the joint aiSion of caloric and light. 



SECTION I. 



O/" the Manner of conducing the Procefs. 

 ELECTRIC difcharges may be employed in two different manners to decompound 

 water. One of tlicfc is by what has been termed the iiilerrupted explfiom which was tJie me- 



I i 2 thod, 



