156 Velocity of the Galvanic Current in Telegraph Wires. 
The agreement of these numbers, I consider very satisfactory. 
It will be observed that the velocity indicated by the St. Lonis 
register is much greater than that derived from the others. Now 
have been proportionate to the greater distance. Those who 
believe the signals to be transmitted throngh the earth (when this 
measurements accord sufficiently well with one another. But- 
when it is remembered that we are dealing with such quantities — 
as hundredths and thousandths of a second, measured too by di- 
but unequal,—we cannot expect any very close accordance, m 
the results of different measurements, f 
Giving the other data more in detail, and determining the prob- 
able errors of the means by the method of least squares, we 
have, es 
St. Louis Signals. 
Register. No. oe | Interval. Prob. error.._| Velocity. Min. lirnit. Max. Iimit_ 
es 37 00373 | 0°00267 15442 6633 
C. 4 0 0844 | 0-00148. | 14748 14494 | 15012 
L. 46 0 °1163 | 0 -00149 12846 
St. L, 3 0°1108 | @-00173 13484 
Louisville Signals. 
Register. | No. obs. Interval. Prob. error. imit. | 
56 00451 000252 
60 00950 000302 1 
L | 65 | 0:1343 000252 | 11124 10919 | 
St. L. 61 01451 000329 14404 14085 
: Cincinnati Signals, 
Reg'ster. | No, obs. Interval, Prob. error. | Velocity, 
P. 33 00283 459 | 20400 
Cc, 32 00752 | 600486 16543 
L. | 32 00750 0:00489 . 16587 
St. L. 26 60704 000442 17670 
