RELATION OF THE REPULSIVE FORCE TO THE QUANTITY OF ELECTRICITY. 431 
the reactive force at 60°, being about the ^th of a grain, that is, about the - ^ -dth 
of a grain for each degree, as already mentioned. 
Table JV. 
Distances. 
Forces with charges 
equally reduced. 
Forces with charges reduced and unequal. 
Degrees. 
Ratio of 
distance. 
1 : 1 
i • i 
4 * 4- 
1:4 
1:4 
1 ' * 
t : 4 
4:4 
4 = 1 
2 
1 
TsT 
46 
Attracted. 
Attracted. 
Attracted. 
3 
.... 
.... 
36 
.... 
62 
30 
55 
29 
16 
6 
i 
T 
.... 
85 
18 
94 
46 
22 
30 
16 
8 
9 
3_ 
125 
42 
8 + 
70 
34 
16- 
14 
8 
4-5 
12 
I 
94 
23 
4-5 
47 
23 
10 + 
8 + 
5 — 
2 + 
18 
3_ 
44 
10-5 
2 + 
20 
10 
5 
3 + 
2 
24 
1 
24 
6 
1 + 
12 
6 
3 
2 
1 + 
48 
2 
6 
1-5 
3 
1-5 
.... 
.... 
.... 
72 
3 
3 
— 
— 
1 + 
— 
— 
— 
— 
.... j 
D 
R 
A 
B 
C 
a 
b 
c 
d 
e 
/ 1 
15. The above Table exhibits the following phenomena, which are not a little 
striking and important. 
1st. It may be perceived, that in columns A and B, the discs being charged equally 
and to a given intensity, the forces vary, (with one or two exceptions only,) in an in- 
verse ratio of the squares of the respective distances : in column A there is only one 
exception, viz. at the distance 9°. When, however, we begin to diminish the quan- 
tity on one of the discs, or charge them unequally, this law is only apparent up to a 
certain limit. Thus at the distance 12° and 6° of columns a , b, and c, as also at 12° 
and 9° of column A, 6° and 9° of column C, the law is in an inverse ratio of the 
simple distance, or nearly approaching to it, whilst within certain limits, and at other 
distances, the law of the force becomes irregular, and is apparently disturbed by some 
foreign influence. Similar results are more or less apparent in all the other columns 
where the quantities of electricity in the repelling bodies are unequal. 
2nd. It is observable that the deviations from the law of ^ are more apparent and 
decided, when the forces are more diminished, the inequality of the respective charges 
greater, and the distance less : under any or all of these conditions, the rate of increase 
of the repulsive forces diminishes, and the repulsion verges toward, and is at length 
superseded by, attraction, as may be seen by a slight inspection of the Table. 
3rd. The quantities of electricity contained in either of the repelling bodies are not 
always proportional to the repulsive forces. Thus in columns B and d the respective 
quantities on one of the bodies are as 2:1, the quantity on the other remaining the 
same, = \ ; but the respective repulsive forces are nearly as 3 : 1, or at least approxi- 
mate very closely to this ratio. The same thing is, in some instances, apparent in 
columns b and d , where the quantities are in the proportions of 1 : and \ : f. W e 
