Students are advised to make the following corrections 

 before reading the book : 



Page 162, 7th Lfrom bottom, the words "as in fig. 46," to be transferred 



to the end of the 1st paragraph on p. 163. 

 464, $th Lfrom bottom, " fig. 124," should be "fig. 125." 

 465, 2nd Lfrom top, "fig. 125," should be "fig. 124." 



