17 



very strong reason for confiding in the absolute fidelity with wliich 

 the observations have been made and transmitted to me. 



TABLE shewing the mean daily motion in inches of the Glaciers of 

 Chamouni deduced from Balinat's Observations, and continued 

 from the Fourteenth Letter. 



1845. Nov. Ifi to Dec. 16 

 Dec. 16 to Jan. 19 



1846. Jan. 19 to Feb. 19 



Intervals of Obserration. 



1847. 



1848. 



Mean Daily Motion in £ng. inchea. 



Bois, Bois, Bossons, Bossuns, 

 No. 1. No. II. No. I. No. II. 



14-0 

 120 

 161 



10-9 

 5-7 

 51 



west aide 



30-2 

 18-8 

 16-9 



6-4 

 100 

 130 



Temp, 



Centigrade 



of Air.* 



-1-47 

 -4-19 

 -0-16 



(Observations interrupted by Balniat's illness.) 



1 eAAt side-l 



Oct. 12 to Nov. 19 

 Nov. 19 to Dec. 20 

 Dec. 20 to Jan. 18 

 Jan. 18 to Mar. 4 

 Mar. 4 to Apr. 12 

 Apr. 12 to May 14 , 373 

 May 14 to July 2 ' 

 July 2 to July 23 ! 

 July 23 to Aug. 16 

 Aug. 16 to Sept. 9 

 Sept. 9 to Sept. 28 

 Sept. 28 to Oct. 18 

 Oct. 18 to Nov. 6 

 Nov. 6 to Nov. 27 

 Nov. 27 to Jan. 10 

 Jan. 10 to Feb. 19 

 Feb. 19 to Apr. 1 

 Apr. 1 to May 3 

 May 3 to June 6 

 June 6 to June 30 



ICtli Oct. Snow 

 at Montaurert. 



Veist quantity of 

 snow. Destruc- 

 tive avalanches. 



Snow disappear- 

 ed on Bossons, 3d. 

 week of May :on 

 Bois, 3d week of 

 -May. 



" I have formerly taken occasion to mention experiments and ob- 

 servations which have occurred from time to time of a nature to con- 

 firm the fundamental hypothesis of the quasi fluidity of the ice of 

 glaciers on the great scale, and I cannot doubt that these incidental 

 remarks have tended to diminish the natural incredulity with which 

 that theory was at first received in some quarters. I have now to 

 cite a fact of the same kind established by a French experimenter, 

 M. Person, who appears not to have had even remotely in his mind 



* Mean of Geneva and Great St Bernard. 



VOL. III. 



