716 
ERRATA 
Proc. N. a. S. 
velopment of seismologic and volcanologic research directly before both 
national and international bodies qualified to furnish advice and promote 
a broad cooperation of great value. 
Yours respectfully, 
Whitman Cross, Chairman, 
WlIvIvIAM Bowi^, 
Arthur L. Day, 
H. E. Grkgory, 
H. FiBlvDING Rkid. 
ERRATA 
9. e. E. D q. e. E. D 
P. 215. For V = read v = — 
47r. rj. I 4-. 7]. I 
P. 268. In theorem II for "but 5fX = 0" read "but B„\ not = 0"; and in theorem 
IV for "or 0 + read "or not = 0". 
P. 416. For the denominator of (1) read 2''p^ where a = ? p'^~Hp~l)\ b = 
2 
- ^(p — 1)2 — 1, and on p. 417 read p^ for the denominator of the second 
2 
fraction and 2° for the left side of the next formula. 
