438 University of California Publications in Geology [Vol. 12 



northerly from the true zero line, and the rate of creep inferred from 

 the curve, .29 meters per year, is in reality somewhat less than the 

 true rate. For, if Ukiah be moving northerly, the increase of latitude 

 due to this cause should not enter into the determination of the mean 

 position of the pole, that is the position of the zero line in relation to 

 the ciirve. 



3. Meridian Circle observations have been maintained at Lick 

 Observatory since 1893 by Astronomer B. H. Tucker, who has kindly 

 supplied me with the following memorandum of the values for the 

 latitude of the station. The results are based on observations both 

 on circumpolar and zenith stars for an average of sixty-eight nights 

 per year during the period from 1893 to 1918, except for the interval 



Average Quarterly Values for the Latitude of Lick Observatory Based on 

 Meridian Circle Observations by Astronomer E. H. Tucker 

 FROM 1893 to 1918 



Epoch 



1893.82 



1894.12 

 .33 

 .51 

 .83 



1895.11 

 .33 

 .63 

 .83 



1896.11 

 .40 

 .67 

 .91 



1897.13 

 .31 

 .72 

 .92 



1898.15 

 .36 

 .83 



1899.12 

 .32 

 .63 



1900.38 

 .89 



1901.46 

 .57 

 .92 



1902.13 

 .37 



Latitude 

 37° 20' 25'.'48 

 .69 

 .47 

 .44 

 .43 

 .61 

 .57 

 .52 

 .56 

 .82 

 .72 

 .43 

 .52 

 .41 

 .47 

 .62 

 .67 

 .94 

 .65 

 .77 

 .86 

 .82 

 .58 

 .73 

 .64 

 .94 

 6.03 

 .71 

 .90 

 .76 



Epoch 



1902.62 

 .88 



1903.12 

 .35 

 .60 

 .92 



1904.11 

 .30 



1905.59 

 . 77 



1906.11 

 .45' 



1907.75 



1908.33 



1912.18 

 .51 

 .75 

 .92 



1913.16 

 ..53 



1914.14 

 .37 

 .63 

 .90 



1917.18 

 .39 

 .62 

 .88 



1918.11 



Latitude 

 20' 26'.'87 

 .68 

 .65 

 .76 

 .88 

 .25 

 .48 

 .76 

 .26 

 .42 

 .58 

 .63 

 .56 

 .18 

 .79 

 .60 

 .38 

 .78 

 .68 

 .32 

 .68 

 .67 

 .52 

 .59 

 .34 

 .58 

 .54 

 .51 

 .55 



