64 Intelligence and Miscellaneous Articles, 



in one of the states just mentioned ; and in tiiis case the experiment 

 as forming a ground of opposition to any of the theories mentioned, 

 becomes altogether nugatory. 



Mr R.'s representation, " that the atoms of the acid have combined 

 with the pure brilliant atoms of the metal, without the necessity of 

 the metal being first converted to an oxide," is at variance with all 

 our knowledge respecting the action upon the metals of solvents con- 

 taining oxygen. 



It is true that some instances are on record of the simple solution 

 of bodies in sulphuric acid, without their oxidation, and that one of 

 these bodies, tellurium, is a metal for the oxide of which the acid has 

 considerable affinity, combining with it to form a crystallizable salt. 

 But in all those cases in which simple bodies are concerned, the acid 

 must be employed in a concentrated state, in order that the effect 

 may be produced ; while water, very gradually added, as when the 

 solutions attract it from the atmosphere, causes the oxidation of the 

 substances dissolved ; or if added quickly, it precipitates them in an 

 uncombined state*. It would appear therefore that no result of this 

 nature can take place in Mr. Ritchie's experiment, since the acid he 

 employs becomes diluted as soon as the experiment commences. But 

 if by possibility the case should be as he represents, a pro|)er exami- 

 nation of the solution of zinc obtained will enable him to determine 

 the fact. 



If it should ultimately appear that the water is not decomposed in 

 Mr. Ritchie's experiment while yet the zinc is dissolved, the solution 

 can take place onlv, in all probability, by the sulphuric acid giving up 

 to the zinc a portion of its oxygen ; and becoming reduced to one of the 

 other combinations of sulphur and oxygen ; while the oxide of zinc so 

 produced will exist in the solution in the form either of hyposulphate, 

 sulphite, or hyposulphite of zinc. And whether such is the case or 

 not, can readily be determined by examining the solution. 



It would appear, therefore, that before this experiment can be re- 

 ceived as conclusive evidence on the point for the determination of 

 which it was instituted by the author, it must be shown that no hy- 

 drogen is extricated during the experiment, or enters into combina- 

 tion with the water or any other substance present ; that the zinc is 

 not in the state of oxide in the solution ; and consequently, that no 

 portion of the water, either of that introduced into the cylinder or 

 of that chemically united with the acid employed, undergoes decompo- 

 sition. To render it perfectly satisfactory, ascertained quantities of zinc, 

 water, and acid, should be employed; it should be ascertained vvhether 

 any, and, if any, how much, of the zinc remains unacted upon, and 

 also whether the entire quantity of water as well as that of acid is re- 

 obtained, either as such, or as combined in any manner with the zinc, 

 after the experiment ; and further, whether hydrogen gas does not 

 escape either during the experiment or on opening the copper cylin- 

 der in order to ascertain the solution of the zinc. 



The above minute examination of Mr. Ritchie's experiment has 

 been entered into, and every possible view taken of the results stated 



* See Phil. Mag. and Annals, N. S. vol. iv. p. 68. 



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