94 THE GERM THEORY OF DISEASE. 



NUTEITION. 



The digestion of nutrition is performed by the tissue itself. 

 When no ferment substance is divisible from the tissue the 

 existence of such substance has been inferred from the phe- 

 nomena observed. We think no one will doubt that the food 

 of the animal goes through further fermentation or digestion 

 after it is taken into the blood, at least, a certain remoleculi- 

 zation, by whatever name it may be called. Is this change 

 brought about in the blood ? Posssibly it is, to some extent, 

 especially during its passage through the liver, the great gland 

 of the blood vascular system, the soluble ferment, or diastase, 

 of which is well known. But the great change is brought 

 about by the tissues themselves. 



In primary digestion there is simply an absorption of other 

 molecules or atoms, by the molecule of the substance under- 

 going digestion, or a splitting up into simpler compounds. In 

 the nutritive digestion (nutrition assimilation) there is a 

 reorganization of the elements into new tissue and formed 

 material. This reorganization is performed in the cells them- 

 selves. The substances are taken into the interior of the cells 

 by osmosis, and then remoleculized by act of the vital force. 

 This is the point, evidently, of the most intimate association 

 of matter with life; it is here that matter is said to be en- 

 dowed with life. 



The products formed here are very definite. The reorgani- 

 zation results in tissue, each tissue selecting and building for 

 itself, and to itself, from the material carried in the blood 

 streams, obtained from the primary digestion and from the 

 lungs. In this reorganization and building by the tissues, 

 definite waste products are given back to the blood streams, 

 namely, carbonic acid and urea. These are cast out by the 

 lungs and kidneys. They are found to be incompatible with 



