424 Dr. R. D. Thomson on DigestioJi. 



porridge and killed three hours afterwards, afforded by the 

 fermentation of 1000 grains '80 carbonate of barytes, = 5'Q 

 grains per pound, or to 2*57 grains of sugar. 



In another experiment the serum of the pig was employed 

 from whose stomach the soluble starch was extracted. 



52027 grains of serum gave 



•68 ... carbonate of barytes, 

 equivalent to 9'01 ... ... per pound, 



4'19 ... sugar 



and estimating the quantity of blood in the human body at 24 

 pounds, by the first experiment we should have 61*68 grains 

 in the sanguineous circulation, and by the second 100*56 

 grains. A pound of urine in diabetes I have found to contain 

 14*361 grains of sugar. Whether the sugar is burned in the 

 lungs and capillaries, or is previously converted into fat by 

 the agency of the casein of the blood, it remains of course to 

 determine; but the experiments of Pelouze have shown us 

 how this may be effected ; and the present determinations seem 

 to form a connecting link between starch and fat, which render 

 the views of Liebig, in reference to the supply of animal fat 

 being derived from starch, still more plausible than was at one 

 time suspected. 



The experiments detailed in this paper appear to lead to 

 the following conclusions: — 



1 . That vegetable albuminous matter and fat when digested 

 can be detected in the blood. 



2. That if any free hydrochloric acid exist in the stomach 

 of animals during the digestion of starch, the quantity must 

 be so minute as to be scarcely appreciable. 



3. That an acid exists in the stomach of animals fed on 

 starch, which corresponds more nearly with lactic acid than 

 with any other known acid. 



4. That dextrin and soluble starch exist in the stomachs 

 of animals which have been fed on farinaceous diet during and 

 for some time after digestion. 



5. That sugar exists in the blood of animals which have 

 been fed on starch. And 



Lastly. It is hoped they have in some measure contributed 

 to throw a ray of light upon the important function which 

 starch fulfils in the animal oeconomy. 



