330 
PEOFESSOE W. THOMSOX AXD DE. J. P. JOULE OX THE 
Seeies X. 
Velocities in the 
alternate experiments, 
in feet per secx)nd. 
Difference 
of thermal 
effect. 
Estimated 
effect of low 
Telocity. 
Thermal 
effect of high 
Telocity. 
Veloc-itT due to 1' C., 
or V j=, on the hypothesis 
that T,o= — . 
* st 
36-3 and 18 
0-045 
0-015 
0-060 
148-2 
51‘o and 18 
0-115 
0-015 
0-130 
142-8 
72-6 and 18 
0-146 
0-015 
0-161 
180-9 
118 and 18 
0-385 
0-015 
0-400 
186-6 
It will be seen from the last column that the effect at slow velocities was En’eater than 
that which might have been anticipated. We w’ere thus led to try the effect of a 
further increase of what we may call fluid 
friction.” In the next series the bulb was 
wrapped with flne iron wire. 
(ici ir: 
Seeies XI. 
Velocities in the 
alternate experiments, 
in feet per second. 
Difference 
of thermal 
effect. 
Estimated 
effect of low 
Telocity. 
Thermal 
effect of high 
Telocity. 
Velocity due to 1°C.. 
or Vjo, on the hypothesis 
tliat V,o= — — 
V t 
15-36 and 7-68 
0-022 
o 
0-008 
0-030 
88-8 
23-04 and 15-36 
0-069 
0-03 
0-099 
73-2 
30-71 and 15-36 
0-118 
0-03 
0-148 
79-8 
46-08 and 15-36 
0-177 
0-03 
0-207 
101-3 
69-12 and 15-36 
0-267 
0-03 
0-297 
126-8 
111-34 and 15-36 
0-530 
0-03 
0-560 
148-8 
126-72 and 15-36 
0-598 
0-03 
0-628 
160 
153-55 and 15-36 
0-850 + 
0-03 
0-880 + 
163.4- 
In the next experiments the bulb was nnapped 
with a spiral of flne brass wire. 
Seeies XII. 
Velocities in the 
alternate experiments, 
in feet per second. 
Difference 
of thermal 
effect. 
Estimated 
effect of low 
Telocity. 
Thermal 
effect of high 
Telocity. 
Velocity due to PC., 
or Y,o, on the hypothesis 
that V ,0= -L. 
i 
7-68 and 1-92 
0-006 
0-002 
0-008 
86-3 i 
15-36 and 7-68 
0-033 
0-008 
0-041 
75-S 
23-04 and 15-36 
0-070 
0-041 
0-111 
69-1 
30-71 and 15-36 
0-105 
0-041 
0-146 
80-3 
46-08 and 19-2 
0-120 
0-075 
0-195 
104-4 
' 76-8 and 23-04 
0-203 
0-111 
0-314 
137-1 
I 115-18 and 23-04 
0-570 
0-111 
0-681 
139-5 
' 148-78 and 76-8 
0-488 
0-314 
0-802 
166-2 
The last columns of the above Tables clearly indicate that at slow velocities a source 
