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would give so high a velocity as 14 kilometers per second. On the suppo- 

 sition that the line of propagation is a chord, a velocity of 9.25 kilometers 

 per second is required, which might more easily })e supposed to be supplied 

 by the high pressure of the deep interior, since pressure seems to increase 

 rigidity faster than it does density (Button's work, p. 234). The most 

 probable path is a chord-like curve convex toward the center of the earth, 

 so chosen automatically by the wave as to give the most effective combi- 

 nation of shortness of path and superior elasticity, since the latter probably 

 increases toward the center so as more than to overbalance the increased 

 density. So far as giving us light on the physical condition of the interior 

 is concerned, it is of the most vital importance that the correct interpreta- 

 tion of the path pursued by the vibrations be entertained. • . 



The address brings out the gratifying fact that collateral investigations 

 on the associated geological conditions, the earth's magnetism, gravity, 

 underground temperature, and other related subjects, are being made 

 by the Earthquake Investigation Committee. They are also engaged in 

 practical studies for the reduction of the disastrous effects of earthquakes, 

 and structural plans for houses are discussed and illustrated in the paper. 



T. C. C. 



Earthquakes in the Light of the New Seismology. By Clarence 

 Edward Button, Major U. S. A. New York: G. P. Putnam's 

 Sons; London: John Murray, 1904. 



This is a very lucid, appreciative, and trustworthy exposition of the 

 recent important advances in seismology, and is in every way a most wel- 

 come contribution to the literature of the earth-sciences. Geologists have 

 only partially realized the profound contribution which the new seismology 

 is in process of making to the fundamental concepts of geology. It is 

 perhaps necessary to guard the statement by saying that seismology is in 

 the process of making, rather than has cdready made, a profound con- 

 tribution to geologic fundamentals, for the contribution is dependent on 

 the correctness of the belief that seismic vibrations pass directly through 

 the body of the earth, as well as around its surface, and that the traversing 

 waves are those that are first recorded by seismographs at distant points on 

 the surface. It cannot as yet be absolutely afl&rmed that these preliminary 

 vibrations actually traverse the deep interior. This is the interpretation 

 of most of the leading seismologists, and is probably the correct one. Still 

 it must be recognized that this is not yet proved, and that Baron Kikuchi 

 (see preceding review) and others hold the view that these vibrations pass 



