THE ORBIT OP URAXUS. 



67 



from observation. To tlie right of these are the equations of condition for the 

 correction of tlie elements. 



A normal equation for he is obtained by ticking the sum of all the equations. 

 That for hi is formed by subtracting the sum of the first seven from the sum of 

 the last seven, and tliose for }e and e\d by taking the sum of the equations in 

 which the coefficients of le or e\j are greater tlian unity, after changing the signs 

 of the equations in which they are negative. The normals thus obtained are 



