THE CONSTANTS OF THE CUP ANEMOMETER. 
10G5 
Table XXIII. 
No. 
Dir. 
Time. 
A. 
A'. 
Log. <p'. 
V . 
v'. 
V. 
T. 
V-V'. 
I. 
s. 
660 
348-5 
677-5 
0-81086 
4-524 
2-931 
12-891 
12-349 
+ 0-542 
IT. 
W. b. N. 
475-4 
131 
237 
0-80236 
2-359 
1-423 
6-836 
6-721 
+ 0-115 
III. 
W. b. N. 
600 
238 
433 
0-80390 
3-399 
2-061 
9-731 
9 037 
+ 0694 
IV. 
W. 
600 
192 
360 
0-80174 
2-742 
1-714 
7-900 
7-761 
+ 0-139 
V. 
S.E. 
540 
458 
940 
0-81188 
7-267 
4-972 
20-623 
20-424 
+ 0-199 
VI. 
S. b. E. 
646-9 
494-5 
1011-3 
0-81938 
6-631 
4-972 
19-088 
20-343 
-1-255 
VII. 
S.W. 
334-8 
227 3 
471 
0-80834 
5-883 
4-063 
16-718 
16-757 
-0-039 
VIII. 
S. b. w. 
600 
300-5 
599 
0-80480 
4-291 
2-851 
12-233 
12-032 
+ 0-201 
IX. 
s.s.w. 
600 
260 
465-5 
0-82025 
3-713 
2-216 
10-616 
9-629 
+ 0-987 
X. 
s.s.w. 
720 
540 
1047 
0-81604 
6-426 
4153 
18-251 
17115 
+ 1-136 
XI. 
S.W. 
600 
286 
593 5 
0-81637 
4-084 
2-825 
11-682 
11-927 
— 0-245 
XII. 
S.W. 
600 
285 
609 
0-81150 
4-070 
2-898 
11-596 
12-223 
-0-627 
XIII. 
S.W. 
420 
316 
638 
0-81497 
6-446 
4-3?6 
18-307 
17-623 
+ 0-684 
XIV. 
s. 
600 
466-5 
910 
0-81140 
6-662 
4-331 
18-915 
17-817 
+ 1-098 
XV. 
w. 
720 
291 
574 
0-80694 
3-462 
2-277 
9-910 
9-839 
+ 0-071 
XVI. 
N.W. 
600 
235-5 
445 
0-80694 
3-362 
2-118 
9-631 
9-255 
+ 0-376 
XVII. 
S.W. b. w. 
511 
463 3 
959-5 
0-79931 
7-767 
5-363 
22-033 
21-883 
+ 0-150 
XVIII. 
S.W. b. W. 
509-1 
395 
883-7 
0-79712 
6-960 
4-957 
20-029 
20-271 
-0-242 
XIX. 
S.W. 
600 
350 3 
727 
0-80133 
5-002 
3-460 
14 235 
14-389 
-0-154 
XX. 
S. b. w. 
491-9 
312-5 
751 
0-80780 
5-443 
4-361 
15-477 
17-937 
-2-460 
The sum of V—-V / = + l'370, Se'= 119’53. Hence Air^ + O'OllI, cc=2'1473, 
z— 3'611 and the limit =4’047. The residue is a little too large; but I did not 
think it necessary to pursue the approximation farther. The great increase of x is 
remarkable, and I think shows that when the cups are so near the axis of rotation 
they disturb the regular action of the wind. Even with the 12" arms this effect is 
sensible. 
(74.) Ej,. I now fixed the 4" cups on the cross at 10"§ from the axis. This arrange¬ 
ment is similar to the 9" cups at 24", and I thought that the same x might serve for 
both, but it was far otherwise. 
The measures in paragraph (27) give for 4" cups a=3’357 at the normal pressure 
and temperature. For the first ten observations y"=35T9 ; but as these cups are 
35*5 oz. lighter than the 9" ones, I thought there was too little pressure on the toe, 
and changed the relieving weight from the 11'5 lbs. to 9 lbs. This made the friction 
= 68‘89. I computed with x=2'57 and s=5'405 Table XXIV. 
6 x 
MDCCCLXXX 
