FOR THE EARTH'S SURFACE. 301 



! 1T-7 ~ A [3 4 -3.2 4 +3. ! 4 -1.0 4 ] + &c. 



1.^.0.4 



1. 1 



4 ' 2~ 4 1 1 . 2 . 3 . 4 

 of 



1.2.3.4. 5 



&c. 



6.2 5 -4.1 5 +1.0 5 ] 



,v. + l 1 



+ , r-r [n n+l -n(n- 1)' 1+1 + &c.l - + &c. 

 (n+l)\ L J J 



Or, employing the symbol of operation A"0 m in the usual sense, 



' Vo'+rf-.s^'+n^s.i*' '^ 



4 2 4 1 . 2 . 3 . 4 



n z 

 ,+ &c. 

 where the first line may be expressed similarly to the rest, viz. 



snce 



AO 1 , AO 2 , AO 3 , &c. are all =1. 



