1 - - 46° 



2 - - 49 



3 - - 52 



4 - - 58 



5 - - 64 



6 - - 72 



7 - - 78 



8 - - 83 



9 - - 88 



58 Laws of the Elementary Voltaic Battery. 



In the first experiment with the heated solution, the average tem- 

 perature was 130°, and the average deflection corresponding was 

 56°. In the next experiment, the mean temp, was 135°, and def. 

 56°. 



22. After removing the plates, and allowing the solution to cool 

 down to 70°, which took place in about three hours, the plates were 

 again plunged, and the lamp reapplied. The following are the re- 

 sults of the deflections for each minute, until the solution reached the 

 boiling point. 



Minutes. Def. Minutes. Def. 



10 - 94° 



11 - 98 



12 - 105 



13 - 110 



14 - 116 



15 - 120 



16 - 126 



17 - 135 

 Boiling, 18 - 145 



From this series it appears, that in the circumstances of our exper- 

 iment the effect of boiling solution is about 3^ as great as that of the 

 same solution at 70°. From the time which the plates are immers- 

 ed, in these experiments, the decline of permanent action must be 

 considerable, and therefore the full effect of the elevated tempera- 

 ture is not perceived. It is probable, that had the solution remained 

 at 70° for the same period of IS minutes, it would have fallen at 

 least 3 or 4 degrees from 46, in which case the energy of the batte- 

 ry at the boiling point would be three and a half times its power at 

 70°. 



23. As it was desirable to obtain several observations at each 

 stage of temperature, a small spirit lamp was now applied to main- 

 tain the temperature constant at each point where the observations 

 were made. The solution in this case was 1 sulphuric acid to 60 

 water. In making the first column of observations, the lamp was 

 withdrawn and reapplied, to ascertain if the deflections were con- 

 stant at the same temperatures. This they seem to be, and the fact 

 would appear to have an important bearing, as pointing to some law 

 which may possibly be found to connect the increase of the deflec- 

 tion with some co-efficient of the temperature. 



