360 



llth. 1858, July 21st. At same Station, No. 2. 



Sidereal chronometer No. 2557, fast: 

 By 7 observations on cc Bootis, VV. (at 



16/i. 37m.) using horizon roof h. m. s. 



No. 1, - - - 1 02 17.31 



By 8 observations on u Cygni, E. (at 



17/i. 19m.) using, also, horizon 



roof No. 1, - - - 1 02 18.39 



By E. and W. stars (at IQh. 58w.) 



with horizon roof No. 1, + 1 02 17.85 h. m. s. 



h 1 02 17.85 



By 8 observations on cc Bootis, W. (at 



16A. 50m.) with roof No. 2, - 1 02 17.68 

 By 8 observations on oc Cygni, E. (at 



17/i. 02m.) also with roof No. 2, 1 02 18.03 



By E. and W. stars (at 16h. 56m.) 



using horizon roof No. 2, + 1 02 17.85 



[- 1 02 17.85 



Result — Chronometer No. 2557, fast of sidereal time 

 for this station (at 16^. 57m.) by 15 observa- 

 tions on ot Bootis, west, and 16 observations on cc 

 Cygni, east, - - - ■ - -f 1 02 17.85 



By comparison — Mean solar chronometer No. 141, 

 slow of mean solar time for this station (at Sh. 

 58m. mean time) - - - - — 4 41.75 



VZth. 1858, September 5th. At Chicago Observing Station No. 3. 



Sidereal chronometer No. 2557, fast : 



By 10 observations on u Coronas Borealis, W. (at h. m. s. 



19/t. 04m.) - - - - - 1 06 53.3 



By 12 observations on ex. Andromeda), E. (at 20A. 



25m.) 1 06 54.7 



Result — Chronometer No. 2557, fast of sidereal time 



for this station (at V.)h. 45m.) - - H- 1 06 54.25 



By comparison — (Jhronomelcr No. 141 , slow of mean 



solar time for this station (at Sh. 45m. mean time), — 4 28.5 



