WIECHERT SEISMOMETERS AT RIVERVIEW COLLEGE. 389 



where the French Missionaries, like their Spanish confreres 

 at Manila, Philippine Islands, have carried on for many 

 years scientific work of a high order in the several depart- 

 ments of Astronomy, Meteorology, Terrestrial Magnetism, 

 and Seismology, and my interest in the study of the last 

 named branch having been aroused in a special way by the 

 fine records of the Calif ornian and Chilian earthquakes of 

 1906, obtained at both of these observatories by very up-to- 

 date seismographs, it was natural enough that on my return 

 to Sydney shortly afterwards, my plans for a College- 

 observatory should turn in this direction, amongst others. 

 I was well aware of the valuable work done for many years 

 in Australasia, as part of a world-wide network of seismo- 

 graph stations, by the standard instrument adopted by the 

 British Association and designed by the veteran English 

 seismologist, Professor John Milne, and I had already had 

 the opportunity of studying its performance at close 

 quarters and appreciating its merits. But the very fact of 

 the Milne instrument being already for some time in oper- 

 ation in Sydney, as well as in Melbourne, Perth, Wellington 

 and Christchurch (the Adelaide one, the best of the six, has 

 only begun work this year), and on the other hand, the 

 high praise given during the last few years by very com- 

 petent authorities in various countries to the performances 

 of some of the more recent Japanese and German seismo- 

 graphs, induced me to adopt one of the latter types of 

 instrument, for the registration of seismic wave-movement 

 here in Sydney. 



It has been my wish that this registration should be of 

 the highest accuracy and sensitiveness, and moreover com- 

 plete, giving the three rectangular components (vertical 

 and two horizontal) and not merely one, and that the records 

 should be used as contributions from New South Wales to 

 the international seismological research-work so actively 



