ityg Experiments with the Galvanic Apparalas. 



the cafe in the broken circuit defcribed by Mr. Nicholfon. When the tubes with gold 

 wires, conne£ted by filver wires, were employed, oxygen was given out in the water con- 

 nefted with the filver, and hydrogen in that commnnicating with the zinc. In none of 

 thefe experiments could any produftion of gas from the mufcular fibre be perceived ; but 

 the parts expofed to the water became whiter than before. 



When (the glafles being connefted with the apparatus by mufcular fibre) the communi- 

 cation between them was made through my body by means of the gold wires in the tubes; 

 one being in contaft externally with my right hand, the other with my left, oxygen was 

 .produced as before in the glafs connedled with the filver, and hydrogen in that conne£led 

 with the zinc. When I made the communication, holding a filver wire partly plunged 

 into the water conneded with the filver, in my right hand, the fingers of my left hand 

 being in the other glafs, the filver wire became flowly oxydated, and no gas was percep- 

 tibly given out in either of the glafles. When on the contrary, I introduced my hand into 

 the filver glafs, and the wire into the zinc glafs, gas was given out round the wire, no 

 oxydation took place, and no gas was extricated in the filver glafs. 



When the glafles were made to communicate both with the machine, and with each 

 other, by means of mufcular or vegetable fibre ; and metallic wires introduced into cither 

 or both of the glafl'es, and wholly or partially covered with water, no gas was given out 

 from them, and no apparent chemical change took place. 



Reafoning on this feparate produftion of oxygen and hydrogen, from difFercnt quan- 

 tities of water, and on the experiments of Mr. Henry, junr. on the a£tion of galvanic 

 eledlricity on difi^erent compound bodies *, I was led to fuppofe, that the confliituent parts 

 of fuch bodies (fuppofing them immediately decompofable by the galvanic influence) might 

 be feparately extricated from the wires, and in confequence obtained diflilnQ from each 

 other. 



a. I filled two of the fniall tubes mentioned in b. i. with ftrong folution of cauftic 

 pot-afh, and inverted each of them in a glafs filled with the fame fubftance ; the glafles 

 were made to communicate with each other by means of mufcular fibre, and the gold 

 wires in the tubes connefted with the ends of the pile. Gas was produced much more 

 rapidly in this procefs from both wires, than in the experiment with fimple water. In 

 three hours no depofition had taken place in either of the glaflies, nor were the gold wires 

 fenfibly aiEled upon. The gas given out in the tube conne<Sed with the zinc, meafurcd 

 cxa£tly 37 grain meafures, and proved to be oxygen abfolutely pure, for with 80 meafures 

 of nitrous gas, containing about -^ nitrogen, it diminiflied to lefs than 3 meafures. The 

 gas given out in the tube connefted with the filver, was equal to rather more than 72 

 grain meafures. It gave no diminution with nitrous gas, and two 20 grain meafures of it, 

 £red with rather more than one 20 grain meafure of oxygen, containing about ,06 nitro- 

 gen, left a globule of air hardly perceptible. 



• Phil, Joum. Vol. IV, p. »i4. 



Surprized 



