ON SEISMOLOGICAL INVESTIGATION. 



59 



Seismolurjical TnvesUrintions. — Seventh Beport of the Committee, consist- 

 inq of Professor J. W. JuDD (Chairman), Mr. J. MiLNE (Secretary), 

 Lord Kelvin, Professor T. G. Bonnet, Mr. C. V. Boys, Professor 

 G. H. Dauwjn, Mr. Horace Darwin, Major L. Darwin, Professor 

 J. A. EwiNG, Dr. R. T. Glazebrook, Professor C. G. Knott, 

 Professor P. Meldola, Mr. P. D. Oldham, Professor J. Perry, 

 Mr. W. E. PluMxMER, Professor J. H. Poynting, Mr. Clement 

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

 (Bi-aicn vp hij the Secretaxi/.) 



Plate I. 



Contents. 



I. 



IT. 

 III. 

 IV. 



Y. 



VI. 



YIT. 



VlII. 



IX. 



X. 



XI. 



XIL 



PAGE 



59 

 60 

 61 



64 



On Sfisiiiu!oi/i<-al Staiions ahroad and in Great Britain .... 



Tlie TtistrvnifiitH in vse at Sliide ......... 



The Uriijins of the Earthqualtes recorded in 1S99, 190O, and J90L 



Buration of tlie FirU Prcliminarij Tremors 



Time Curves for E'lrthqiialu-s recorded during the four years ending 



December i\ . \900 65 



The Com pari son of the Ihcords ohtaitied from three horizontal pcndiihnns 



at SMde . ' 68 



Clivometrie Experiments .......... 70 



Vertical Spring Seismograph Experiments ....... 71 



On the Mature ot Earthquake Morement ....... 71 



Eelatioiiship hetn-een, Hochfilding, Seismic, and Volcanic Activities . . 72 

 On the Comparison of Earthquake Registers from SMde, Kew, Bidston, and 



Edinhurgk . . . . ■ • •' • ■ ■ • .73 



Expenments at the Ridgen-ay Fault. By HOEACB Darwin . . .75 



I. On Seismological Staiions abroad and in Great Britain. 



Seismographs of the type recommended by the Seismological Investiga- 

 tion Committee of the British Association have been constructed for and 

 in most instances are already established at the following stations : — 



The last registers issued by the British Association Committee are 

 Circulars Nos. 4 and 5. These refer to Shide, Kew, Bidston, Edinburgh, 



