OF ARTS AND SCIENCES : JANUARY 10, 1865. 



385 



X = 42 42 30.73 



Correction for level -|~3.30 



" for azimuth — 0.35 



" for declination -|-1.02 



X 42 42 34.75 



The great part of my observations were lost by clouds, which would 

 come up unexpectedly and spoil the labor of four hours, again and again. 

 I have on some nights made as many as twenty observations, involving 

 four hundred passages in the E. V., without getting a single star in the 

 W. v., thus losing all. I can, therefore, rest the latitude of Williams 

 College on only fifty-two observations, but hope these may be enough 

 for present purposes. 



Let X'= (latitude of P. V. instrument — 42° 42' 20"). 



X be the value of one division of the level, which Mr. Phelps thinks 

 to be near 1".0. 



Values oi aV -\- a' X — h = Q. 



(A.) {From Observation.) 



