178 Reviews — Frof. Milne's Seisrnological Journal. 



probably never bave been detected, and would, tberefore, bave 

 appeared in the final result." 



The value obtained for the mean density of the earth is 54934, 

 and will now no doubt take its place as the standard value. Sooner 

 or latei', perhaps, unsuspected sources of en-or may be pointed out, 

 methods of greater refinement may be discovered, and the result 

 just quoted may be superseded by others more reliable. For the 

 present, one more " magnificent experimenter " has given the thought 

 of years to a problem that lies just within our grasp, and we may 

 well rest content with a work which is one of the best examples we 

 have of the fine patience that ennobles science. 



C. Davison, 



IV. — The Seismological Journal of Japan, Vol. II. 1893 (corre- 

 sponding to vol. xviii. of the Transactions of the Seismological 

 Society of Japan) : Edited by Prof. J. Milne, F.R.S. 



(1) J. Conder. An architect's notes on the great earthquake of October, 1891: 



pp. 1-91. 



(2) J. Milne. Abstract of a report [on the earthquakes and volcanic phenomena of 



Japan] to the British Association : pp. 93-109. 



(3) E. von Rebeur-Paschwitz. On the observations of earthquake- waves at great 



distances from the origin, with special relation to the great earthquake of 

 Kumamoto, July 28th, 1889: pp. 111-114. 



(4) P. Mayet. On the five mile water-level: pp. 115-117. 



(5) F. Omori. On the overturning of columns : pp. 119-122. 



The first and last papers of this invaluable Journal are chiefly 

 interesting to architects in earthquake countries. Prof. Milne gives 

 an abstract of his last report to the British Association, the full text 

 of which will probably be published and readily accessible before 

 this notice appears. Dr. Mayet advocates the construction of the 

 long water-level suggested by Prof. Milne in the first volume of the 

 Journal, but the latter adds a note in which he prefers the erection 

 of horizontal pendulums at what would be the terminal stations of 

 the level. 



In a short paper Dr. von Rebeur-Paschwitz introduces a subject 

 of great importance. The severe earthquake of Kumamoto (Japan) 

 occurred on July 28, 1889, at 11.40 p.m., Tokio time, or 2h, 20-9m., 

 Greenwich time. At about 2-28 p.m. (a.M.T.) horizontal pendulums 

 at Potsdam and Wilhelmshaven, in Germany, showed perturbations 

 of moderate size and duration, and others, again, somewhat similar 

 in character, at 6*6 p.m. Supposing the disturbance to have spread 

 out from Kumamoto and travelled in opposite directions round a 

 great circle of the earth to a point midway between Potsdam and 

 Wilhelmshaven in the times recorded, the average velocities in 

 the two directions must have been 2-2 and 2-3 kilometres per 

 second respectively. The hypothesis thus agrees with the observed 

 phenomena, but " we will have to depend on future observations to 

 remove the last doubt about the possibility of earthquake movement 

 being observable at enormous distances." — 0. D. 



