IMRODUCTORY ADDRESSES, 141 



German Cliemist has rendered himself illustrious by his discoveries and 

 inductions in this department, and if he has not always secured approba- 

 tion for his speculations, he has unquestionably contributed largely to 

 the advance of Chemical Science. 



Dr. Atlce, making use of the discoveries of this eminent Chemist, 

 sho.ws what are the agents, what is their composition, and which are re- 

 lated to the nutrition and support of animal existence. Some of them 

 are adapted to renew the waste of vital operations, to resupply the loss in 

 the various structures of the body. They are the nitrogenized food, or 

 as Dr. Liebig calls them — the plastic elements of nutrition. They alone 

 are supposed "capable of conversion into blood, and of assimilation to 

 the various organs and tissues, and containing a peculiar principle, cal- 

 led proteine, essential to existence." There are the non-nitrogenized, 

 or "elements of respiration, and are supporters of respiration and ani- 

 mal heat. " 



Saj's Dr. Atlee, "although this peculiar principle, proteine, exists in 

 the plastic elements of nutrition, it has no separate and distinct exis- 

 tence in organic structure, but is associated with mineral and organized 

 substances, constituting fibrine, albumen, and caseinc, the so called pro- 

 teinaceous or nitrogenous aliments. Proteine, consists of carbon, hy- 

 drogen, nitrogen and oxygen. Add sulphur, and wc have Caseine. 

 Add sulphur and phosphorus, and Albumen is the product. Reduce the 

 quantity of sulphur in the albumen, and Fibrine is formed, so that pro- 

 teine is the base of all these alimentary principles." 



In these substances, or their elements, constituting nitrogenized food, 

 we have the constituents of the human body, except fluorine. "Pereira," 

 says Professor Allee, "is of opinion that if fluorine is a normal con- 

 stituent of the body, it is introduced into the system in the small 

 portions of the bones of animals occasionally swallowed with their 

 fle.sh, Berzelius having delected minute quantities of fluoride of calcium 

 in the bones of animals." 



The importance of proteine is very great. On it depends the or- 

 ganic structures — "the organic nitrogenized constituents of the body — 

 which are formed from it by the agency of oxygen or the elements of 

 water, and by resolution into two or more compounds." The ques- 

 tion become interesting : What is the source of this proteine, which 

 plays so important a part in the animal economy ? 



Here we will let our author speak: "Recent researches of Chemi- 

 cal philosophers have disclosed the beautiful and important fact, that the 

 proteinaceous compounds are alone produced in the vegetable organism,' 

 and tliat the various tissues of the animal body depend for their forms- 



