150 
MR. DANIELL ON VOLTAIC COMBINATIONS. 
No. 4. Battery connected 20 E. 
Unconnected 50 E. 
Again connected 40 W. 
Again unconnected ..... 50 E. 
Again connected 40 W. 
changed to 30° E. 
and swang violently E. & W. 
No. 5. Battery connected 35 E. 
Unconnected 55 E. 
Connected . oscillated E. &W. 30 
Hence it appears that this variable current may be produced from the single cells 
of the battery, under ordinary circumstances, when the whole series is connected by 
short wires. 
I was still desirous of ascertaining whether these currents would be produced in the 
simplest possible arrangement, viz. when the elements consisted of amalgamated zinc, 
copper, and dilute sulphuric acid. For this purpose the five cells were thoroughly 
cleaned, and charged entirely with standard acid, without sulphate of copper. They 
were connected in series with a voltameter, and each cell was separately tested by 
the galvanometer, with the following results : 
Time. 
Interval. 
Voltameter. 
5 min. rate. 
Galvanometer. 
1 56 
61 
5 
If 
Cell 1.- 
-45° E. 
2 6 
10 
3 
Cell 2.- 
-45 E. 
11 
15 
4 
1 
Cell 3.- 
-40 E. 
16 
20 
A3 
Cell 4.- 
-40 E. 
21 
25 
°2 
of 
Cell 5.- 
-40 E. 
The voltameter was removed, and the circuit completed by a short wire : the sepa- 
rate cells were again tested, with the following result : — 
Cell 1.-25° E. 
Cell 2.— 20 W. 
Cell 3.— 20 W. 
Cell 4.— 25 W. 
Cell 5.-25 E. 
When the cells 2, 3, and 4, whose secondary currents were all W., or in the direc- 
tion opposite to that of the main current, were all included in the secondary circuit, 
the deflection of the needle was 30° W. ; but the current produced no decomposition 
in the voltameter when included with them. The deoxidation of the oxide of copper 
by the hydrogen was thus proved not to have been the exciting cause of the se- 
condary currents. 
I was now desirous of making a comparison of all these effects with the similar 
