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CALIFORNIA ACADEMY OF SCIENCES. 



V\ The difference between the mean equator point and 

 the mean nadir point is the supplement of the latitude. 



The following table furnishes a brief summary of the 

 results derived from the observations of each night: 



The mean of the results Clamp W. is 37° 20' 24''. 6; the 

 mean for Clamp E. is 37'° 20 25". 2, showing a slight dis- 

 -cordance between the results derived from different posi- 

 tions of the instrument. Such a discordance wsls a 2^rio7i 

 probable, having been found in the case of other meridian 

 circles. 



The most probable value of the latitude that can be de- 

 rived from these observations, is the mean of the results 

 Clamp W. and Clamp E. : 



37° 20' 24".9, 



which may be adopted as a provisional value for the latitude 

 of the center of the mercury basin of the meridian circle. 

 The probable accidental error of this result, estimated from 

 the discordances of the individual results, is not far from 

 dz 0."10, but the above value of the latitude provisionally 

 assumed, may be affected by systematic errors arising from 

 defective graduation of the circles, flexure, irregular refrac- 

 tion, etc., amounting in the aggregate to a considerably 

 greater quantity. 



The north dome of the Lick Observatory is twenty-seven 

 feet north of the meridian circle, whence its latitude results 

 from these determinations, 37° 20' 25". 2. 



Mr. C. A. Schott, Chief of the Computing Division of the 

 U. S. Coast and Geodetic Survey, has kindly communicated 

 results for the position of this station, Avhich have been 



