417 



effecting the expansion of the ice in the smallest degree. This would 

 of course be still more applicable if we take the mean of the tempe- 

 ratures at Chamouni and the Col du Ge"ant to present the general 

 atmospheric conditions to which the glacier is exposed. 



It is in summer that the glacier moves fastest : it is with my 

 observations of motion in July that Mr. Moseley compares the results 

 of his theory : and therefore it is of no avail to say that there are 

 periods of the year when congelation penetrates at night some inches, 

 or even it may be some feet into the ice, and when therefore the 

 sensible heat of the glacier may be considered to vary, though, if 

 regard be had to its vast thickness, it must be on an average and in 

 the most extreme circumstances to an absolutely inappreciable 

 degree. 



Lastly, Mr. Moseley, whilst condemning in the following passage 

 the theory of glacier motion by the dilatation of water in the inter- 

 stices of the ice, clearly passes sentence on his own, which could not 

 come into action until the other had already produced its effects : 

 " The theory of Charpentier, which attributes the descent of the gla- 

 cier to the daily congelation of the water which percolates it, and 

 the expansion of its mass consequent thereon, whilst it assigns a 

 cause which, so far as it operates, cannot, as I have shown, but 

 cause a glacier to descend, appears to me to assign one inadequate 

 to the result ; for the congelation of the water which percolates the 

 glacier does not, according to the observations of Professor Forbes, 

 take place at all in summer more than a few inches from the sur- 

 face. Nevertheless it is in summer that the daily motion of the 

 glacier is greatest." (Moseley, Proc. R.S. vol. vii. p. 341.) 



II. " Researches on the Foraminifera. Part I. General Intro- 

 duction, and Monograph of the Genus Orbitolites." By 

 WILLIAM B. CARPENTER, M.D., F.R.S., F.G.S. &c. 

 Received May 21, 1855. 



The group of Foraminifera being one as to the structure and 

 physiology of which our knowledge is confessedly very imperfect, 



