534 
THE RESULT OF M’GAULEY’S EXPERIMENTS. 
accounts for the former not being 
double the weight of the latter. 
lb. oz. 
Magnet No. 1. with keeper No. 1 
lb. oz. 
lifted 25 3^ 
2.. 8 Hi 
3 *39 3i 
4 39 3i 
3 25 3i 
2 . 7 3 
1 .30 2i 
Magnet No. 1, with keeper No. 2, 
lifted 32.11; an accidental stirring of 
the battery accounts for the increase. 
Magnet No. 4, with keeper 
No. 1, lifted 84 3i 
2 26 3 
1 .... 24 2i 
2 .... 15 3i 
Sixth Series. 
To test, with as much accuracy as 
possible, the comparative excellence of 
various charges, he tried the following 
experiments. The galvanometer con- 
sisted of small, but exceedingly good, 
electro- magnet m, a * battery, b, two 
inches square, single cell, zinc plate 
i inch thick at commencement of ex- 
periments, and a delicate needle, n, 
made to stand at zero when the battery 
was not connected with the magnet. 
The least magnetism produced by con- 
necting the battery with the magnet, 
tended to deflect the needle. He pre- 
ferred this galvanometer, on this occa- 
sion, to the ordinary one, for many rea- 
sons. The battery was well cleaned af- 
ter each charge. The first deflection 
on connecting the battery with the mag- 
net, carefully noted the number of de- 
grees at which the needle rested, and 
the decrease of deflection every quarter 
of an hour for six quarters. Rain-w'-ater 
was used. The specific gravity of the 
sulphuric acid 1840; nitric acid 1410; 
muriatic 1175. 
The solution of caustic potash con- 
tained 2 in 7^ of the liquor. 
* See plate iv fi g 4-. 
TAifLE OF RESULTS OF THE EX P E It 1 11 1- N iS. 
1 in 
Rain water and niiiic acid .. I in 2 I parts .... 
I ill 3i 
I ill 41 
I in 51 
Rain water and sulphuric acid I in til 
I ill 31 
1 in 41 
1 in 51 
Rain water and muriatic acid l in 4l 
1 in 51 
Solutions of caustic and potash 
Rain water & suipb. acid 1 in 4l| nitric I in 
1 in 26| 
1 in 161^ 
I in 2011 
Rain water and muiiat.. 1 in 52 sniph 
nitric 
1 in 5‘2^ sniph 
Solution of caustic potash, and sulph. 
and iiiiric 
and nniiiat 
Sea waterfioni Dublin Bay 
Sea watei & sulpliuiicacici.. 
and nitric ac:d.. .. 
Rain watei and nitric, I in 53, sulph 1 in 53 
and muiiat. 1 in 53 
1 in 40.=-, 
I in 52 
I ill 52 
1 in to 1 
Mil 51 
I in 
1 III 
I in 
I in 
First Deflection, 
Needle settled doivn to 
1 Deflection in \st quar- 
ter decreased to. 
1 
/n 'Ind quarter. j 
■ 5 = 
n* 
908 
52® 
32i® 
11^® 
4f® 
3 %^ 
38 
•-i'l 
15^ 
13 
64 
Sk 
46 
46 
31 
H 
3g 
H 
38 
84 * 
m 
75 
5 
3 
88 
44 
15i 
13| 
9 ^ 
84 
H 
49 
3(ti 
10 
5 
4 
67 
44 
15 
8| 
4 
4| 
4 
33t 
‘24 
3| 
3 
U 
0 
97 
33^ 
73 
H 
8 
0 
0 
58 
•22i 
9 
H 
0 
0 
0 
80 
19 
7 
H 
98 
-iS 
24 
II 
7| 
6 
H 
82 
40 
•24 
154 
85 
H 
23^ 
S()| 
4 
•1 
k 
0 
50 
23 
H 
0 
0 
0 
0 
35 
25 
44 
11.5 
6-1 
•28* 
15 I 
10 
0 
85 
46^ 
10 
6 
85 
0 
0 
88 
4.5 
H 
If 
4 
0 
0 
43 
0 + 
0 
0 
0 
0 
0 
23 
Is 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
83 
26 
13 
8 
f)| 
H 
0 
95 
55 
33^ 
16^ 
0 
0 
95 
59 
40 
16 
iO 
3 
0 
In two minutes it ran up to 85®, settled down to 51®. 
t Would not deflect the needle even with renewed charge, 
