454 Experiments to determine variations in length 
Comparisons of 8, and Z, at the temperature of melting ice—cowd. 
Micro-readings. 
Date Time. | Bar Observer. Remarks. 
F | Ww 
1883. 
Feb. 10) 7.59pm.| S, | 28°374| 23-979) E.S. W. |Both bars have presage ei onesie 
8.12 1 345| 24°126 in ice since 12.21 P. 
21 1 028] 23-825 
25 4 052 649 
35 1 27 901| R. 8S. W. 
38 1 684) 24°507 
50 1 ae 212 
54 1 564 179 
Feb.11)10.42 am | S, 526) 24°192| E. S. W. ee hse has emerge packed 
49 1 | 591} 460 ce during past night. 
58 i 231| 100 Steel co was Bares in ice about 
11.03 1 283 28 . M. 
08 i 486| 24°139| R. S. W 
13 iy 5TT 8 
23 by 859 T1T 
26 1 833 493 ‘ 
Feb. 12} 8.00e.m.| S, 126; 090 Both bars were packed in ice at 
03 iy 006 013 7.30 P. M. 
08 1 259 267 
11 2 273 42 
13 4 122 080) FE. 8. W. 
15 208 48 
2) 1 208 258 
Ms ; vt cae f the ice at 
o 
waa re alg rn MESO ree by isteand left compen 
36 ty | 27°990| 23°850) was then taken into a room where the 
39 1 | 28-386) 24-446) ee ee ete ae. Lt wae 
rr ia i R.S. W. |yempeFature of alr in comparing-room 
47 GY 534 383. iSteel bar was fully packed in ice at 8.00 
50 : 340] 4211 hvee 
The foregoing include all the comparisons which have thus 
far been made of the zinc and steel bars. 
The mean differences in length of the two bars for the vari- 
ous sets of comparisons are given in the following table. Their 
probable errors are derived from the discrepancies between the 
mean and individual differences resulting from successive com- 
parisons in a set. 
