56 



II = .2953 

 tlic units einiiloyetl Iieiiig the cm, ^Tanuiie and second. 



Another series of three complete determiuatioiis gave as a mean ; 



II = .3012 

 And the mean of all gives — 



II = .2975 



Since these observalinns wens completed I have been tbrtunale in being able, 

 to secure the results of two other determinations of the Imrizontal component 

 (if the earth's magnetisni, made in this vicinity and with apjiliance.s which arc, 

 in the main, far nmre ]ierfect than those which Mr. Fujisawa was obliged to 

 drpend upon. For one of thivse I am indebted to the kimlncss of Commander 

 Sampson V. S. N., who made a series of observati<.ins during the past sunnner 

 in the yard of the Ü. S. Consulate at Yokohama. As determined by Conunauder 

 Sampson the value is; 



H = .29592 



Tlic other is to be found in a memoir recently ]iublished by Herr Otto 

 Scluitl of the Geological Sm-vey who made a deti/rminalinn in Tnkio, also during 

 the past summer. The value there given is; 



H = .30742 



It will thus be seen that the value found by Mr. Fujisawa lies between 

 these tw'o determinations and it may probably be regarded as not far from the 

 truth. 



In August both of the magnets, (A), and (!>), were carried to the sununit 

 of Fujinoyania and were vilirated there by Mr. Fujisawa, the period being deter- 

 mined in the s;\me manner as in Tolcio. It was necessary to cany on the 

 magnetic experiments in the .same small hut on the summit of the mountain 

 in which the instruments for the gravitation determination were mounted and as 

 the Chronograph was almost constantly in us(^ in connection with the latter, it 

 was found to be impossible to make more than two complete series of vibrations 

 with each magnet. As soon as possible, after the return of the party and the 

 instruments to Tokio, the nmgnets were again vibrated in order to ascertain what 

 change, if any, had occurred in their magnetic condition during their absence. 



The t'ollowing are the mean results at different times and places. 



Date Place Time of vibration 



,.luly 1 Tokio 10.(;2S 



(A )] August, 5 Summit of Fnjinoyama.,.. 10.903 



'vAugu.st 21 and 22 Tokio 10.t;4S 



/July 6 Tokio 9.531 



(?>)< August 5 Siunmit of Fnjinoyama.... 9.S27 



'Ausust 24 Tokio 9.570 



