456 
MR. W. CROOKES ON THE SUPPOSED 
smoke of burning camphor. On re-suspension, the following series of experiments was 
tried : — 
No. of 
experiment. 
Material of pillar. 
Maximum 
speed of one 
revolution. 
No. of 
revolutions. 
Exciting agent. 
]0 
Polished ivory. 
seconds. 
21 
4-25 
Face 
11 
18 
4-25 
Hot water 
12 
Boxwood wedge, edge to cylinder . 
11 
575 
Face 
13 
15 
5-5 
Hot water 
14 
Polished brass tube. 
20 
4-25 
Face 
15 
Polished square brass rod, flat side to 
37 
2-75 
99 
16 
cylinder 
Polished square brass rod, edge to 
16 
6-5 
99 
17 
cylinder 
Polished brass wedge, edge to cylinder 
i* 
7-5 
99 
18 
7 
17-5 
Hot water 
19 
Glass rod, 65 mm. long, P5 mm. thick 
11 
5 
Face 
20 
21 
4-25 
Hot water 
21 
Brass wire, 60 mm. long and 0'5 mm. 
20 
225 
Face 
22 
diameter 
Brass wire, 60 mm. long and 0 - 5 mm. 
24 
2-5 
Hot water 
23 
diameter 
Platinum wire, 65 mm. long and 0'4 
61 
2-25 
99 
21 
mm. diameter 
Platinum wire, 65 mm. long and 0‘4 
34 
4-5 
Face 
25 
mm. diameter 
Fine glass fibre, 65 mm. long . . 
0-5 
99 
26 
46 
1-5 
Hot water 
27 
Single fibre of cocoon silk, 50 mm. long 
075 
Face 
28 
99 99 99 
29 
2-0 
Hot water 
This series of experiments having shown a decided increase of motion due to 
blackening the cylinder, another series was tried with the pillars as well as the cylinder 
coated with the soot from burning camphor. 
