368 Miscellanies. 



Those who knew Davy, will best conceive the enthusiasnn with 

 which this hasty record of his success was dashed off, and will re- 

 cognize sup7];<a in his " capital experiments !" — Ibid. 



5. Decomposition of Water by Atmospheric and by common EleC" 

 tricity. — Mr. Bonijol, conservator of the reading society of Geneva, 

 has constructed many very delicate apparatus, by means of which 

 water may be readily decomposed by the electricity of the ordinary 

 machine, and also by atmospheric electricity. The electricity of the 

 atmosphere is gathered by means of a very fine point fixed at the ex- 

 tremity of an insulated rod ; the latter is connected with the appara- 

 tus, in which the water is to be decomposed, by a metallic wire, of 

 which the diameter does not exceed half a millemeter, {j\ of an 

 inch.) In this way the decomposition of the water proceeds in a 

 continuous and rapid manner, notwithstanding that the electricity of 

 the atmosphere is not very strong. Stormy weather is quite sufficient 

 for the purpose. M. Bonijol has also succeeded in decomposing 

 potash and the chloride of silver, by placing them in a very narrov/ 

 glass tube, and passing a series of electric sparks from the ordinary 

 machine through them. The electricity was conducted into the tube 

 by means of two metallic wire's fixed into the ends. Where a quick 

 succession of electric sparks had taken place for about five or ten 

 minutes, the tube containing chloride of silver was found to contain 

 reduced silver ; and where potassa had been submitted to the elec- 

 tric current, there the potassium was seen to take fire as it was pro- 

 duced. — Ibid. 



6. On the state of Chlorides, Iodides, &fc. in solution. — Carlo Mat- 

 teuci, decomposed the Chlorides and Iodides, by means of the pile, 

 with the expectation of being able to deduce the nature of these com- 

 pounds when dissolved in water. If it were possible to decompose 

 these combinations by means of electric currents, incapable of de- 

 composing water, one might then justly conclude that their composi- 

 tion was not changed by solution in that liquid. He, therefore, took 

 a pile composed of two elements only, charged with water rendered 

 slightly saline, and which had no power of decomposing water even 

 a little acidulated. The platina conductors were then dipped in a so- 

 lution of muriate of copper, and after some time, the negative con- 

 ductor was covered with metallic copper, whilst the positive conduc- 

 tor evolved bubbles of gas. Having replaced the latter conductor 



