724 
Proceedings of the Royal Society 
giving the time of the greatest phase 
18 11 52 m 57 s . 6. 
and the greatest eclipse 200". 
By this very short operation, we have solved the quadratic and 
substituted the value of its root in the cubic equation. 
Counting the time in minutes from 19 h 20 m , the equation for 
the last contact is 
+ -0015^ 3 - -1865** - 13-098& + 11*7 = sep n = 0 . 
+ -0092 
- -3730 
+ 83 
-13-0983 
- -3357 
+ 37 
+ 11-7000 
- 11-7885 
- -1510 
+ 11 
o- 
+ ‘9 
+ *0092 
- *3747 
-13-4303 
+ 66 
- -2384 
+ -2417 
+ •9 
- -018 
+ "0033 
+ -882 
showing that the eclipse will end at 
19 h 20 m 52 s, 9 Green. M. S. Time. 
Should favourable weather allow of a good observation, I shall 
compute the times for my own place, and submit the comparison 
to the Society. 
3. Some Experiments on a New Secondary Cell. 
By Mr. A. P. Laurie, B.Sc. 
Last summer I communicated a paper to the Society on an 
Iodine Cell. This cell consisted of a carbon and zinc rod 
immersed in solution of iodine, in iodide of potassium. I found 
that iodide of zinc was equally suitable to dissolve the iodine in, as 
mentioned in that paper. While experimenting with this cell, 
the idea occurred to me of using it as a secondary battery. When 
