390 Dr. C. Davison—Founders of Sersmology— 
out in the same state of civilization, while other countries have 
emerged from a state of semi-barbarism.! 
Soon after the foundation of the Seismological Society, Milne 
began the systematic study of the distribution of Japanese earth- 
quakes. He adopted the plan of distributing bundles of postcards 
among the Government offices in all important towns within a 
hundred miles of Tokyo. Every week a postcard was to be returned 
to him with notes of any earthquakes observed. The results of two 
years (1881-3) were enough to show the efficiency of the method 
(387 earthquakes were recorded during this time in north Japan), 
and to reveal the principal laws of distribution. The “ barricade of 
postcards’ was then extended northwards as far as Sapporo, 
450 miles from Tokyo, but the labour and expense were becoming 
too great to be borne by one man, and the Imperial Meteorological 
Depaztment, with its 968 reporting stations, was induced to carry 
on the work. The materials for the eight years 1885-92 were 
afterwards placed in Milne’s hands, and thus enabled him to prepare 
his great catalogue of 8,331 earthquakes recorded in Japan during 
these years. 
The value of this catalogue and the immense labour involved in 
its preparation can only be appreciated by those who, like myself, 
have spent some time in analysing its contents. For convenience 
of printing, the catalogue is in two parts. Together they give, for 
every earthquake, the date, the extent of the area disturbed, and 
the lengths of its axes, the position of the epicentre, and, when 
submarine, its distance from the nearest coast.? 
Distribution of Japanese Earthquakes—It was characteristic of 
Milne that he left the discussion of his great catalogue for the most 
part to other workers. He was mainly interested himself in studying 
the distribution of the Japanese earthquakes in space. For this 
purpose he divided the map of the whole country into more than 
two thousand rectangles by north-south and east-west lines one- 
sixth of a degree of longitude and latitude apart. These rectangles 
are all numbered, and the position of the epicentre in the catalogue 
is indicated by the number of the rectangle in which it lies. On the 
map, the epicentres are represented by dots spread uniformly over 
each rectangle, and it is seen at once that these dots are grouped 
in fifteen districts with definite boundaries, except that, in two 
districts, the shocks were so numerous that the boundaries are 
represented as straight lines beyond the proper limits, as there would 
not otherwise have been room to insert the dots.® 
1 Milne’s catalogue of great Japanese earthquakes has been superseded by 
“ The Earthquake Investigation Committee Catalogue of Japanese Harth- 
quakes ’’, compiled under the superintendence of the late S. Sekiya (Journ. 
Coll. Sci., Imp. Univ., Tokyo, vol. 11, 1899, pp. 315-88, with a discussion by 
F. Omori, pp. 389-437). 
pie Trans., vol. 3, 1881, pe. 65-102 ; vol. 4, 1882, pp. 1-30; vol. 7, pt. 2, 1884, 
pp. 1-87; Journ., vol. 4, 1895, pp. i-xxi, 1-367. 
2 Another method of pene: the distribution of these earthquakes is 
illustrated in the Geogr. Journ., vol. 10, 1897, pp. 530-35. 
