Manchester Memoirs, Vol. /. (1906), No. 7- 31 



expected, since we may give either sign 'o the radical, or what 

 is the same thing, the solution for {a - r) is the same as that 

 for {r- a). 



Table III. 



Hence the density falls at first, being infinite at the surface ; 

 but when r=2R it ceases to decrease and begins to increase, 

 becoming infinite again when r ■= 2a - H or r= 3 A". 



NOTE V. 



The variation in height attained for different velocities 

 follows at once from the equation 



V = p 



For vertical projection, the maximum height, given by v = o, is 

 r=2a. Suppose this is one radius {R) from the surface, or 



