196 
PROFESSOR GRAHAM ON OSMOTIC FORCE. 
Table IV. — Sugar in Osmometer E of double membrane for five hours. 
I. 
II. 
hi. 
IV. 
V. 
VI. 
VII. 
Sugar iu 
solution. 
Rise in 
millimeter 
degrees. 
Same in 
grammes 
of water. 
Diffusate of 
sugar in 
grammes. 
Previous 
maceration. 
Hydrostatic 
resistance. 
Temperature, 
Fahr. 
per cent. 
0-25 
5 
0-240 
davs. 
2 
min. 
10 
63 
0-25 
9 
0-420 
0-050 
1 
10 
63 
1 
12 
0-531 
0-110 
1 
8 
66 
1 
11 
0-472 
0-106 
1 
10 
66 
2 
24 
1-060 
0-205 
1 
8 
67 
2 
31 
1-357 
0-208 
1 
8 
69 
5 
65 
2-891 
0-600 
2 
8 
72 
5 
63 
2-773 
0-555 
1 
8 
70 
10 
89 
3-953 
1-073 
1 
10 
67 
10 
104 
4-602 
0-967 
1 
10 
67 
10 
96 
4-248 
1 
10 
67 
20 
133 
5-900 
1-457 
1 
10 
67 
20 
106 
4-720 
1-643 
10 
10 
64 
20 
118 
5-251 
1-656 
1 
6 
64 
1 
19 
0-826. 
0-105 
1 
6 
68 
1 
19 
0-826 
1 
6 
65 
2 
24 
1-062 
0-153 
1 
6 
65 
2 
25 
1-121 
0-162 
1 
6 
64 
5 
37 
1-652 
0-435 
2 
8 
66 
5 
33 
1-425 
0-470 
1 
8 
67 
10 
69 
3-068 
0-757 
2 
8 
67 
10 
76 
3-363 

1 
8 
69 
20 
110 
4-807 
1 
8 
70 
20 
112 
4-956 
1-540 
2 
3 
70 
The diffusates of sugar (Column IV.) were obtained by evaporating the fluid of the 
water-jar to dryness, at 212°, and therefore contain organic matter dissolved out of 
the membrane ; the weight of each of the diffusates is increased by this addition a 
few thousandths, but not in such a quantity as to affect the result to an extent that 
is at all material, except in the first diffusate recorded, that from the 0*25 per cent, 
solution. 
Although the results exhibit several irregularities, yet starting from the 1 per cent, 
observation, in the first series of Table IV., the amount both of osmose and diffusate 
appears compatible with an arithmetical progression in the observations from 1 to 10 
per cent. Thus the average rise in the 1 per cent, solution is 11*5 millimeter degrees, 
and in the 10 per cent, solution 96'3 ms.; the average diffusate in the 1 per cent, 
solution is 0'108 gramme, and in the 10 percent, solution T020 gramme, 
But with the 20 per cent, solution both osmose and diffusate fall off greatly, and 
the osmose more than the diffusate. The osmose of the 20 per cent, solution may be 
taken as 125 ms., — the mean of the first and third observations, 133 and 118, the in- 
termediate observation 106 being obviously exceptional, possibly from the unusually 
long maceration of the membrane immediately preceding that experiment. Hence 
the osmose only rises from 96'3 ms. to 125 ms., while the proportion of sugar in the 
osmometer was increased from 10 to 20 per cent. 
