432 



Mr. G. H. Darwin. On the [June 16,. 



that I have done upon this last subject. Observations conducted under 

 varied physiological conditions require to be undertaken, so that 

 besides having the facts as mere chemical facts before us, we may be 

 in a position also to deal with them from a physiological point of view. 

 In a subsequent communication, I will enter further into this matter ,. 

 and then supply details of the actual quantitative results. 



Summary of Conclusions. 



Bernardin (glycogen) does not undergo any significant transforma- 

 tion into sugar in contact with blood. 



Bernardin exists to a distinctly notable extent as a normal consti- 

 tuent of blood. 



The evidence derivable from the observations recorded on the 

 addition of Bernardin to blood and its subsequent recovery, and on its 

 extraction from the liver by boiling water on successive days, and by 

 water at 300° F., tends to show that Bernardin enters into feeble com- 

 bination with nitrogenous matter. 



Bernardin exists in notable amount, not only in muscle, as has been 

 previously known, but also in the spleen, pancreas, kidney, and brain. 

 These are all the structures I have yet examined. It also exists in 

 notable amount in the white and yolk of egg. These several products 

 likewise contain a cupric oxide reducing substance, which is extracted 

 by alcohol, and which, in most instances, possesses the characters of 

 glucose, but, specially in the case of muscle, the characters of maltose- 

 Through the existence of Bernardin (glycogen) throughout the 

 system, as has been represented, we have a carbohydrate occupying 

 a parallel position to albumen, viz., existing in the colloidal state, and 

 thus adapted for retention within the body, instead of passing off as a 

 diffusible substance as glucose tends to do. 



XVIII. " On the Stresses caused in the Interior of the Earth 

 by the Weight of Continents and Mountains." By G. H. 

 Darwin, F.R.S. Received June 11, 1881. 



(Abstract.) 



In this paper I have considered the subject of the solidity and 

 strength of the materials of which the earth is formed from a point of 

 view from which it does not seem to have been hitherto discussed. 



The first part of the paper is entirely devoted to a mathematical in- 

 vestigation, based upon Sir William Thomson's well-known paper on 

 the rigidity of the earth.* The second part consists of a summary 

 and discussion of the preceding work. 



* " Thomson and Tait's Nat. Phil.," § 834, or " Phil. Trans.," 1863, p. 573. 



