JExperments with Volta^^ Galvanic Apparatus. 225 



.: Bxp» VL By employing gold on both fides M. Richter ob- 

 ferved that there were formed bubbles of air arifing from the 

 two wires. He obferved alfo that the air-bubbles which 

 ^rofe from one of the wires were larger than thofe from the 

 other; and he thence concluded that the fpecific gravity of 

 the one kind of air mull be greater than that of the other. 



Exp, VIL M. Richter endeavoured tofeparate the two airs, 

 and for that purpofe invented the apparatus reprefented by 

 fig. 2. He introduced two gold wires into a marble veflel 

 filled with water, and applied the zinc at a and the filverat^; 

 the wire^ w^^ about q,n inch diftant from the wire b. He 

 clofecj the chain, and found, after fixteen hours, that the 

 bell ^, which he had fufpendcd over a, contained one part of 

 air J while thie bell ?^^ fufpendcd oyer b, contained two an4 

 a half; 



'By putting phofphorus into the air s, he faw vapour? 

 formed, which became more abundant in proportion as the 

 operation advanced, and the volume of air at the end of fix 

 or eight hours was diminifhed. There remained only about 

 a third part:, it is not impoflible that 4 portion of azotic gas 

 was difengaged from the water during the experiment. 



The air in w, which occupied about a cubic inch, being 

 inflamed as it paffed in large bubbles into the atmofphere, 

 detonated with the fame force as a mixture of equal parts of 

 hydrogen and atmofpheric air. 



M.Ilichter had placed two glaflfes, d: and 2;, below the wires: 

 that placed under b contained fome metallic parts, arifing, in 

 all probability, from a little copper contained in the gold. 



The two gafes when placed together produced water, as 

 ufual, on an ele61:ric fpark being made to pafs through them, 



Exp, VIIL By employing on the fide b, zinc, tin, copper, 

 charcoal, and plumbago, M. Richter always obtained hydrogen, 

 provided the wire brought into contact with the zinc of the 

 apparatus was of fuch a nature as not to become oxydated. 

 He employed alfo, inftead of gold, charcoal, plumbago, and 

 cryfiallifed oxyd of mangauele at a and bi the phrenomena 

 were alwavs the fame as well as when he placed platina at a^ 

 keeping the gold, charcoal, plumbago, and oxyd of manga- 

 nefc at b, 



Exp, 



