344 



Report of the Keio Observatory Committee. 



standard eye observations for the control of the automatic records 

 have been duly registered. The monthly mean values are given in 

 Appendix II. 



The tabulations of the meteorological traces have been regularly 

 made, and these, as well as copies of the eye observations, with notes 

 of weather, cloud, and sunshine, have been transmitted, as usual, to the 

 Meteorological Office. 



With the sanction of the Meteorological Council, data have been 

 supplied to the Council of the Royal Meteorological Society, the 

 Institute of Mining Engineers, and the editor of ' Symons' Monthly 

 Meteorological Magazine.' 



Eledrograph. — This instrument worked generally in a satisfactory 

 manner during the year. 



The " setting " of the electrometer needle, mentioned in last year's 

 ' Report,' has been considerably reduced, and the working of the instru- 

 ment improved, by the removal of the large glass cup, with a diameter 

 of 100 mm, — used for holding the sulphuric acid — and the substitution 

 for it of a small glass beaker, with a diameter of 40 mm., resting 

 upon a disc of paraffin, and containing about 35 c.c. of acid. The acid 

 and accumulated moisture is removed at frequent intervals. 



Scale value determinations were made on January 24, May 12, 

 July 21, and November 7, and in addition the potential of the battery 

 has been tested weekly. Forty cells only have been employed through- 

 out the year. 



A battery of thirty-six Clark cells has been purchased from Messrs. 

 Muirhead on behalf of the Meteorological Council, with the hope of 

 thereby introducing greater certainty into the interpretation of the 

 records. 



With the sanction of the Meteorological Council, the electrograms 

 for the year 1897 have been lent to Mr. C. T. R. Wilson, of Sidney- 

 Sussex College, Cambridge. 



Inspections. — In compliance with the request of the Meteorological 

 Council, the following Observatories and Anemograph Stations have 

 been visited and inspected : — Stonyhurst, Fleetwood, Armagh, Dublin, 

 Valencia, Falmouth, and Fort William, by Mr. Baker ; and Radcliffe 

 Observatory (Oxford), Yarmouth, North Shields, Glasgow, Aberdeen, 

 and Deerness (Orkney), by Mr. Constable. 



III. Seismological Observations. 



Professor Milne's " unfelt tremor " pattern of seismograph has been 

 maintained in regular operation throughout the year; particulars of 

 the time of occurrence and the amplitude in seconds of arc of the 

 largest movements are given in Appendix III, Table 1. 



The disturbance (No. 145) on September 10 was particularly notice- 



