ERRATA. 



Page 88, Line 24, read a — p x instead of a-p i2 (1) 



Page 92, Line 26, read -845 ; 5 instead of 



J] n (n - 1 ) i , 



• 84 ^j^5iy} ( 19 > 



Page 103, Line 6, read 539" instead of 559". 



