288 EXPERIMENTAL INVESTIGATIONS. 



dried, and weighing when dry 9*6 grains, was passed up 

 through the liquid into the large tube of a gas battery by 

 means of a small loop of mica, which kept it separated both 

 from the glass and the platinum ; the tube was now charged 

 with pure nitrogen, and the associated tube with pure oxygen, 

 the level of the gases or water-mark being noted by a little 

 slip of paper pasted on the tube ; a check experiment of 

 oxygen and nitrogen without phosphorus was charged at the 

 same time ; the whole was carefully closed from the atmo- 

 sphere and set by for twenty-four hours in closed circuit, to 

 get rid of any current from adventitious circumstances ; the 

 next day, when tested by the galvanometer and iodide of 

 potassium, a very decided action was apparent in the phos- 

 phorus battery, the iodide being decomposed and the galva- 

 nometer needle swinging round to 30, the nitrogen with the 

 phosphorus representing the zinc of an ordinary voltaic com- 

 bination ; the check experiment gave not the least deflection 

 or decomposition. The experiments were suffered to remain 

 in closed circuit for four months, from August 10 to De- 

 cember 14, 1844, having been frequently tested in the in- 

 terim, and the galvanometer always evidencing a continuous 

 voltaic action in the phosphorus battery. On the I4th of 

 December the water in the oxygen tube having by its rise 

 denoted the absorption of a cubic inch of oxygen, plus the 

 slight quantity 0*05 cubic inch of oxygen due to solution, as 

 proved by comparison with the second battery, the experi- 

 ment was examined : the result was as follows : 



Rise of liquid in oxygen tube, I cubic inch. 



in nitrogen tube, o. 



Original weight of phosphorus, 9-6 grains. 

 Present weight of phosphorus, 9'2 grains. 



The battery was again charged in a similar manner, and 

 put by on December 19, 1844; the phosphorus weighed 

 2*8 grains. This, in consequence of the extremely cold 

 weather which has prevailed almost without intermission from 

 that time to the present period, proceeded much more slowly, 

 and was not examined until May 17, 1845, when the results 

 were as follows : 



