92 REPORTS ON THE STATE OF SCIENCE. 



Seismological Investigations. — IJleventh Report of the Committee, consist, 

 ing 0/ Professor J. W. Judd (Chairman), Mr. J. Milne (Secretary), 

 Lord Kelvin, Dr. T. G. Bonney, Mr. C. Vernon Boys, Sir 

 George Darwin, Mr. Horace Darwin, Major L. Darwin, Professor 

 J. A. EwiNG; Dr. E. T. Glazebrook, Mr. M. H. Gray, Professor 

 C. G. Knott, Professor R. Meldola, Mr. R. D. Oldham, Professor 

 J. Perry, Mr. W. E. Plummer, Professor J: H. Poynting, Mr. 

 Clement Reid, Mr. Nelson Richardson, and Professor H. H. 

 Turner, (Drawn up by the Secretary.) 



[Plate L] 

 Contents. 



PAGE 



I. General Notes on Stations and Registers 92 



IL T]ie Situation of Stations ........,, 93 



III. The Origins of Large Earthquakes in \^QB 94 



IV. Large Earthqualtes in relation to Time and Space 95 



V. Relationship of Large Earthqualtes to each other and to Volcanic Eruptions 97 



VI. Earthquakes and Changes in Latitude ....... 97 



VII. On the Change of Level on t7w sides of a Valley 99 



VIII. Antarctic Eartliquakes 100 



IX. JSote on the Betermination of the Time of Origin of Earthquakes. By R. D. 



Oldham 100 



X. Biurnal Changes in Level in Maiiritius. i?y T. F. Claxton . . .102 



I. General Notes on Stations and Registers. 



The registers issued during the past year are Circulars Nos. 12 and 13. 

 They refer to Shide, Kew, Bidston, Edinburgh, Paisley, Toronto, 

 Victoria (B.C.), San Fernando (Spain), Ponta Delgada (Azores), Cape of 

 Good Hope, Alipore, Bombay, Kodaikanal, Batavia, Perth, Trinidad, 

 Christchurch, Cairo, Irkutsk, Baltimore, Beirut, Honolulu, Cheltenham 

 (Md. U.S.A.), and Vieques (Porto Rico). 



From the United States Coast and Geodetic Survey the Secretary has 

 received records from the Milne pendulum established in Honolulu, 

 together with records from Bosch-Omori pendulums installed at Vieques 

 (Porto Rico), Cheltenham Md. U.S.A., and Sitka. 



These registers appear in Circular No. 13. 



Records have not yet been received from Melbourne, Sydney, and Are- 

 quipa ; while registers from Tokyo, Wellington, Philadelphia and Mexico 

 should be brought up to date. The Seismological Committee of the British 

 Association would be greatly indebted to the Directors of Observatories 

 at these places if they would kindly forward copies of their observations. 



During the last year Milne pendulums have been installed at Old 

 Frensham Hall, Haslemere, Surrey, at the University in Malta, and at 

 the National Observatory in Paris. 



All instruments record photographically on cylinders moving at the 

 rate of 25 cm. per hour. The two first instruments are single component, 

 while the latter gives a two- component record. The insti-ument at 

 Haslemere was established by the late Hon. Charles Ellis, who, in 

 addition to giving this assistance to observational seismology in this 

 country, forwarded to the Secretary a cheque for 200^., to be used as he 

 considered best to assist seismological research. Your Committee suggest 

 that it be employed towards the general expenses at Shide station, 



