IO4 



TABLE 84. ACCELERATION OF GRAVITY. 



For Sea Level and Different Latitudes. 



This table has been calculated from the formula g^ =& [i .002662 cos 2<f>]* where $ is the latitude. 



* The constant .002662 is based on Harkness' data (Solar Parallax and Related Constants, Washington, 1891). 

 The acceleration of gravity for any latitude <f> and elevation above sea level h is very nearly expressed by the equation 



g$=sv& (i -002662 cos 2<t>) [_ l ~ji( l ~~Tb)j* 



where R is the earth's radius, 8 the density of the surface strata, and A the mean density of the earth. When 5=o 

 we get the formula for elevation in air. For ordinary elevations on land is nearly J, which gives for the correction 

 at latitude 45 for elevated portions of the earth's surface 



eu-^ 98o.6X^- = 1225.75 cm. per sec. per sec. 

 4R 4/c R 



=386.062 X 5* =482.562 in. per sec. per sec. 

 4R R 



=32.1719X^=40.2149 feet per sec. per sec. 

 +R R 



This gives per 100 feet elevation a correction of 



.00588 cm. per sec. per sec. ) 



.00232 in. per sec. per sec. > diminution. 



.000193 feet per sec. per sec. ) 

 SMITHSONIAN TABLES. 



