361 



l^th. 1858, September 1th. Same Station, No. 3. 



Sidereal chronometer No. 2557, fast: 



By 9 observations on a, Andromedce, east (at 207i. h. m, s. 



24w.) - - - - - 1 07 06.7 



By 15 observations on x Lyrce, W. (at h. m. s. 



22h. 2l7n.) - - - 1 07 06.51 

 By 8 observations on ec Aqui'se, also 



W, (at 22h. 2Sm.) - - 1 07 06.53 



By 23 observations on 2 West stars 



(at 22h. 22m.) . - 1 07 06.52 



1 07 06.52 



Result — Chronometer No. 2557, fast of sidereal time 



for this station (at 2lh. 23m.) - + 1 07 06.62 



Bi/ comparison — Chronometer No. 141, slow of mean 



solar time for this station (at 10/i. 15m. mean time) — 4 28.36 



I would have preferred « Coronee Borealis, W. for combination 

 with oc Andromedce, E., as they are nearly of the same north declina- 

 tion, but clouds in the early part of the night obscured him. 



Rates of the Chronometers. 



As the rates of the two chronometers are necessarily introduced 

 into the computations, it is proper that they should be here exhibited 

 as derived from the foregoing observations made at Chicago. 



They are as follows, viz. — 



VOL. VI. — ,) D 



