8 
th e apparatus, and the amount of the pressure was measured 
by a column of mercury in an open manometer. There was 
some difficulty in measuring the volume owing to the 
occasional escape of bubbles of gas, which caused abrupt 
alterations of the level. The results obtained are given in 
the following table, which also contains a column of volumes 
calculated on the supposition that the amalgam is a mere 
mixture of fluid mercury and gas, allowance being made for 
the pressure on the gas due to the column of mercury in the 
amalgam itself. The extreme case was assumed, namely, 
that this additional pressure is represented by a column of 
mercury half the height of the amalgam. 
No. of 
Experiment 
; 
Volume of 
mercury 
in the 
amalgam. 
Atmospheric 
pressure in 
centimetres 
of mercury. 
Volume of 
amalgam 
under 
atmospheric 
pressure. 
The 
increased 
pressure in 
centimetres 
of mercury. 
Observed 
volume of 
amalgam 
under 
increased 
pressure. 
Calculated 
volume of 
amalgam 
under 
increased 
pressure. 
6 
c.cm. 
14*5 
76-2 
c.cm. 
21-0 
152*4 
c.cm. 
18*0 
c.cm. 
17*9 
7 
11-9 
76-8 
23-0 
188*2 
17*5 
17*1 
8 
11*9 
76-8 
22-7 
200*9 
17*0 
16*4 
9 
24-4 
76-2 
36-2 
152*4 
31*6 
30*9 
10 
24-4 
76-2 
31-6 
152*4 
28*0 
27*4 
11 
13-2 
76-2 
28-7 
152*4 
23*0 
21*6 
12 
13-2 
76-2 
22*5 
152*4 
18*5 
17*2 
13 
10-4 
76-2 
18-0 
186*3 
14*7 
13*7 
14 
10-4 
76-2 
16-0 
186*3 
12*8 
12*8 
15 
23-8 
76-2 
40-4 
178*7 
33*6 
31-9 
16 
23*8 
76-2 
42-0 
176-1 
33*6 
32-7 
17 
23*8 
76-2 
42-8 
152*6 
35*0 
34-7 
18 
23-8 
76-2 
40-4 
177-4 
33*3 
31*9 
19 
23-8 
76-2 
42*2 
102*6 
38*8 
38*5 
20 
23-8 
76-2 
42-2 
153*6 
34*0 
34*0 
21 
23-8 
76-2 
42-2 
177*4 
33*0 
32*7 
22 
23-8 
76-2 
42-0 
201*5 
32*2 
31*6 
23 
23*8 
76*2 
40-2 
177-4 
32*2 
32*1 
24 
23-8 
76-2 
40-6 
201*5 
31*2 
30*6 
25 
23-8 
76-2 
36-2 
149*5 
32*6 
30*6 
26 
29-2 
76-2 
42-0 
177-4 
36*8 
35*4 
27 
29-2 
76-2 
42-0 
200*2 
36*2 
34*7 
28 
29-2 
76-2 
40-6 
173-6 
36*0 
34*7 
29 
29*2 
76-2 
39*5 
198*9 
34*4 
33*4 
30 
24-6 
76-2 
32*0 
155*9 
29*7 
28*4 
31 
24-6 
76-2 
340 
177-4 
30*4 
28-7 
