260 Prof. Latham, On the formation of lactic acid, [May 11, 



The chief objection to the formula which I have suggested for 

 albumen is "that it consists of a large number of molecules in 

 molecular as distinguished from atomic combination ; and on the 

 whole, organic molecules seem to have extremely little tendency 

 to enter into this kind of combination." This objection is fatal to 

 my formula, but stimulated by the kind expressions of the writer of 

 this criticism I did not relinquish the subject, and I hope to show 

 now that a further step has been gained towards the solution of 

 the problem. 



When proteid substances are decomposed or when they are 

 introduced into the alimentary canal and digested, certain amido- 



acids, or glycines, such as glycocine CH 2 \ p n( 4-rr , leucine 



C * H "{cOOH' ^ rosine C ^|c 2 H 3 (NH 2 )COOH &C -' are pro " 

 duced, these substances are absorbed into the system and thereby 

 the waste of the tissues is repaired. Now these glycines are capable 

 of uniting with each other (Hofmeister) and it is probable that 

 their molecular weights are at least double as great as their 

 formulse would indicate*. They may be represented by the 

 formula 



C H 2 . NH 3 . O . CO 



I" ' I 



CO.O-NH 8 .CH 2n 



To obtain these substances from albuminous tissues the tissue 

 must be hydrated, i.e. a certain amount of H 2 must enter into 

 chemical combination with the tissue. On the other hand, we 

 know that glycogen in the liver is obtained by the dehydration of 

 glucose in the alimentary canal, and the question therefore suggests 

 itself; — what compound would result from the dehydration of these 

 other bodies with which we are now concerned, the glycines ? From 

 two molecules of glycocine dehydrated we should have 



90hP H - -oh ( nh * 



glycocine (CO . NH - CH 2 - COOH 



PH 2 



CI M 



^CO. NH + HO 



OH J 



" (COOH 



* Miller's Chemistry, 1880, Part in. p. 866. 



