VOLTAIC ACTION OF PHOSPHORUS, SULPHUR AND HYDROCARBONS. 357 



having a long solid leg (see fig. 1), was placed a small piece of solid sulpimr ; this 

 was held in the large aperture of a gas batteiy cell, while the tube was passed care- 

 fully over it ; the platinum in this tube was connected with the zinc of a single cell of 

 the nitric acid battery, while an anode of platinum was placed in the liquid through 

 the central aperture; by this means all the oxygen of the atmospheric air was 

 exhausted, and the surplus hydrogen was in turn taken away by connection with 

 the associated tube charged with oxygen ; the same effect might have been more 

 slowly produced by the process described (29.). The sulphur was now in an atmo- 

 sphere of pure nitrogen, and this could have been effected in no other way that I am 

 aware of without wetting or forming some deposit on the sulphur. Having connected 

 it in closed circuit with the oxygen tube for twenty-four hours, the galvanometer gave 

 no deflection. A small hoop of iron with a handle was now heated and passed over 

 the tube containing sulphur and nitrogen, the wires being connected with the galva- 

 nometer (see fig. 2). The result was very striking : I had directed my assistant to 

 watch the galvanometer while I attended to the manipulation. At the same instant 

 he exclaimed that the galvanometer was deflected, and I that the sulphur was melt- 

 ing; the galvanometer continued deflected during the whole time that the sulphur re- 

 mained fused, and indeed some time afterwards, until all the sulphur vapour diffused in 

 the nitrogen had become exhausted. The sulphur represented the zinc of an ordinary 

 voltaic combination. It was of course impracticable in this case to ascertain the 

 equivalent consumption. This experiment very strikingly exhibits the analogy of 

 sulphur with phosphorus, and proves that the instant sulphur is fused it becomes a 

 volatile body, as phosphorus is when solid ; the suddenness of its action, coupled 

 with the insoluble character of sulphur, leads to the conclusion that solution in the 

 electrolyte is not a necessary antecedent to voltaic action in the gas battery. Indeed 

 this might have been deduced from the experiments with phosphorus, as its vapour 

 must have been nearly, if not absolutely insoluble in the electrolyte, or the equivalent 

 results would not have come out so accurately ; possibly solution and electrolysis are 

 in these cases synchronous. 



(43.) I was now led to try in the gas battery other substances differing from phos- 

 phorus and sulphur, but possessing characters which had hitherto prevented their 

 being used as voltaic excitants; as, if my view of the volatility of phosphorus 

 and sulphur were correct, other volatile bodies ought to act similarly. Camphor 

 was the first substance I experimented on. A piece of camphor weighing 12-9 grains, 

 was placed in a similar manner to the phosphorus (33.) in nitrogen, and associated 

 with oxygen ; tested by the galvanometer it gave a feeble deflection, which, however, 

 was continuous ; it was allowed to remain four months in closed circuit; at the 

 expiration of that time the liquid had risen in the oxygen tube 0*3 cubic inch ; the 

 nitrogen in which the camphor was suspended had increased in volume 015 of a 

 cubic inch. The camphor weighed 11*4 grains, but some minute crystals of it were 

 observed at the top of the tube, so that the loss of weight was greater than that due 

 to voltaic action. 



