116 



1st Result — Chronometer fast (at 16A. h. m. s. 



52m.) - - - 1 45 42.66 h. m. s. 



h 1 45 42.66 



2d Set. 

 By 7 observations on ^ Hercules, and . 

 11 observations on <^ Cygni, both 

 east (at 16^. 04m.) - - 1 45 42.74 



By 9 observations on s Bootis, west 



(at 17/i. 25m.) - - 1 45 42.50 



2d Result — Chronometer fast (at IQJi. 



45m.) - - - 1 45 42.62 



+ 1 45 42.62 



Result adopted — Chronometer No. 2557, fast of si- 

 dereal time for this station (at 16^. 48m.) + 1 45 42.64 



The above result for the Madison time, and the results of the obser- 

 vations for the time at Chicago on the 3d and 6th of June, 1859, 

 already given in tlieir proper places, combined with the following tele- 

 graphic signals, give us a new result for the longitude of Madison, as 

 follows, viz. — 



Determination of the difference of Longitude between Chicago and 

 Madison, Wisconsin, by electric signals for compai'isons of time, 

 June Uh, 1859. 



Sidereal Chronometer No. 2557, fast, of Madison sidereal time (at 

 15/t. 51m. 45s. sidereal time), \h. 45m. 42&-.43. 



Rate per sidereal day, + 65.O86; or per sidereal hour, + Os.2535. 



Mean solar Chronometer No. 141, slow, of Chicago mean solar 

 time (at 11 A. 12m. 24s. mean time), 4m. 44s.42. 



Rate per mean solar day, — 0s.20; or per mean solar hour, — 

 Os.0083. 



1st. — Chicago signals recorded at both stations. 



Times of 

 si^riiila given 



at Chicaj^o 



by mean solar 



Chronometer 



No. 141. 



Correct 

 Cbi(Mf;o 

 mean solar 

 time of 

 Chicago 

 signals. 



h. m. s. 

 11 07 40 

 11 10 40 

 11 25 40 



h. m. s. 

 11 12 24.42 

 11 15 24.42 

 11 30 24.42 



Times of 



Chicago 



signals, as noted 



at Madist)n 



by sidereal 



Chronometer 



No. 2657. 



h. m. s. 

 17 43 28 



17 46 28.5 



18 01 31 



DifTerence of 

 Longitude by 

 each signal. — 



Madison is 

 west of the me- 

 ridian of Chi- 

 cago observing 

 station No. 3. 



h. m. s. 

 07 02.36 

 07 02.36 

 07 02.39 



1st Mean. — Electric signals sent from Chicago to Madison, 



07 02.37 



