CORRECTIONS. 



P. 7, line 35. — For fiind, read find. 



P. 115, line 11 from bottom. — For (56) read (55). 



P. 120, line 4 from bottom. —For 1.502 X10 10 read 1.502 X10 7 



P. 125, line 23. — For by, read be. 



P. 160. Equation (41) and preceding equation for Cp read C p . 



(See Vol. XIII.) 

 P. 165. line 29. — For a, read or. 



