172 THERAPEUTICS AND PHARMACOLOGY 



activity may do harm instead of good to the body as a whole. 

 What is requisite for health is an harmonious action of all the dif- 

 ferent parts of the body, or as St. Paul very well puts it, "And thus 

 all the body framed and knit together through that which every 

 joint supplieth, according to the working in due measure of each 

 several part, maketh the increase of the body unto the building up of 

 itself" (Ephes. iv, 16, Revised Version), so "that there should be no 

 schism in the body and that the members should have the same care 

 one for another." No doubt in their long wanderings together Luke 

 the beloved physician discussed physiology largely to Paul, and his 

 expression is so good that I introduce it now. 



Just as the people of a country is composed of individuals, so the 

 body is composed of numerous cells. The whole class of microbes 

 consists of isolated cells which are like a nomad population, each 

 individual complete in himself, and all ready to form a swarm for 

 attack and invasion. The cells which compose the body, on the con- 

 trary, are mostly fixed, and differ from each other in structure and 

 function, but ought all to act together for the common good, like 

 civilized people. Each cell lives in the fluid which surrounds it, blood 

 or tissue juice, from which it takes what it needs for its own nutriment 

 and pours back the products of its tissue activity which may be partly 

 waste and partly manufactured products of the utmost utility. 



In order to have a complete comprehension of therapeutic prob- 

 lems it is necessary that we should know something about the life of 

 the cell, because the life of the whole body depends upon that of the 

 cells which compose it, and the cure of disease and the preservation 

 of life depend on our power to influence cell-life. The processes of life 

 are to a certain extent the same in the human body as a whole, in the 

 cells which compose it, and in the smallest living organisms or mi- 

 crobes as they are termed. They all digest and assimilate food, they 

 all breathe, and they all excrete waste products. A knowledge of the 

 processes of life in man helps us to understand them in low organisms 

 and vice versa. The use of pepsin and pancreatin in indigestion 

 is so common that almost everybody knows that these substances 

 have the power of dissolving meat and that pancreatin converts 

 starch into sugar. Everybody knows that these are got from the 

 stomach and pancreas of animals and that it is by similar substances 

 formed in our own digestive canal that we are able to dissolve the 

 food we eat and render it fit for absorption. It has recently been 

 found that pancreatic juice, as poured out by the gland which secretes 

 it, is very slightly active, but it is made active by another ferment 

 secreted from the intestine which is called enterokinase. The pan- 

 creatic juice contains several ferments; that which acts upon meat 

 is called trypsine and in its inactive state it is called trypsogen. 

 The action of the enterokinase on the trypsogen may be compared 



