PROFESSOR DANIELL ON VOLTAIC COMBINATIONS. 
153 
will place this in a striking 1 point of view. The voltameter consisted of five pairs of 
platinum plates, each four inches by 3% inches, at an average distance of half an inch 
apart. These were so arranged that any number of them might at pleasure be con- 
nected with a battery. 
20 cells of the small battery were so arranged as to form a series of 5 quadruple 
cells, and then connected with one pair of plates of the voltameter. By a mean of 
two experiments they gave 26*2 cubic inches of gases for five minutes. 
When all the plates of the voltameter were connected with the battery, the product 
of gases for five minutes was 32 cubic inches. 
The same battery arranged to form a series of 20 single cells, furnished with one 
pair of plates 16 cubic inches, and with all the plates the result was the same.. 
Now by experiment, if E = 1 , e — 2*49, R = 1 , r — resistance with one pair. 
( 1 .) 20 with one pair 
* 
( 2 .) 
20 with five pairs 
20 — 2-49 
20 + r 
20 - 2-49 
T 
20 + 4 - 
5 
( 3 .) 
5 quadruple with one pair 
17*51 
20 + r 
= 16 cubic inches. 
17*51 
V 
20 + — 
5 
2*51 
1-25 + r 
16 cubic inches. 
26*2 cubic inches. 
( 4 .) 
5 quadruple with five pairs 
5 - 2-49 
2-51 
T 
1*25 + — 
5 
= 32 cubic inches. 
Since the electromotive forces in the two last expressions are the same, we can, by 
comparing them, ascertain the value of r. Thus 
1*25 + r : 1*25 + y : : 32 : 26*2 
18*125 1 , 
r = “52 T- = ¥ nearl ¥ 
Now substituting this value of r in the expressions ( 1 .) and ( 2 .), and adopting the 
experimental result of 16 cubic inches, we obtain for 
Calculation. 
17*51 
( 1 .) the fraction 20^33 = 16*2 cubic inches. 
17*51 
( 2 .) the fraction ^qq = 16*0 cubic inches. 
The calculated results it will be seen almost coincide with each other, as do the ex- 
periments. 
By the substitution of different values for R and r in the formula, it will be found 
that every different arrangement must have a distinct number in series, which it will 
be most advantageous to work with, and this number will vary in the same arrange- 
ment, with the nature of the electrolyte, and also with the size of the battery plates. 
It will appear from calculation, that the most advantageous combination is that in 
MDCCCXLII. X 
