1886. } Recent Literature. 949 
RECENT LITERATURE. 
Mitne’s EarTHQuakEs!.—This is a very timely work in view of 
the recent earthquake at Charleston. For this reason we shall 
for the use of our readers, abstract some of the leading points 
relating to earthquakes and their causes, which seem generally 
accepted and to accord with observed facts. While it is estimated 
that several earthquakes occur daily throughout the world, refer- 
ence is also made to the smaller movements called “ earth tre- 
Motion is discussed theoretically, Mallets and Abbot’s results 
aid given as well as the results obtained by the author in 
apan, 
A single shock is, as Mallet states, an impossibility. His 
statement is quoted as follows: “ The almost universal succession 
of phenomena recorded in earthquakes is, first a trembling, then 
a severe shock, or several in quick succession, and then a trem- 
bling gradually but rapidly becoming insensible.” 
the results of observations on the velocity of propagation of 
an earthquake it appears that in the Tokio earthquake of October 
25, 1881, the disturbance must have traveled between Yokohama 
and Tokio at the rate of 4300 feet per second, but from Hakodate 
to Tokio at a velocity of 10,219 feet per second. Thus Milne 
Concludes from his own observations and those on the Lisbon and 
other earthquakes, that: 
I. Different earthquakes, although they may travel across the 
Same country, have very variable velocities, varying between sev- 
hundreds and several thousands of feet per second. 
2. The same earthquake travels more quickly across districts 
se its origin than it does across districts which are far re- 
o 
s Ta The greater the intensity of the shock the greater is the 
velocity, 
_ Multiplied observations show that however chaotic at first sight 
Earth , professor of minin 
å quakes and other Earth Movements, By JOHN MILNE, professor of mining 
Peal ef in the Imperial College of Engineering, Tokio, Japan, With thirty-eight 
` New York, D. Appleton & Co, 1886. 12mo., pp. 363. 
