THE AUTOGENOUS DISEASES. 483 



astrous, and with the effects of non-elimination we are fairly con- 

 versant. Of the myriads of cells in the healthy human body there 

 is none which is superfluous. It is true that among these ultimate 

 entities of existence death is constantly occurring, but in health 

 regeneration goes on with equal rapidity and each organ continues to 

 do its daily and hourly task. The microscope has made us familiar 

 with the size and shape of the various cells of the body, and pathol- 

 ogists have described the alterations in form and size characteristic 

 of various diseases ; but we must remember that in the study of these 

 ultimate elements of life there are other things besides their morpho- 

 logical history to investigate. They are endowed with life, and they, 

 as well as bacteria, have a physiology and a chemistry which we but 

 slightly know. Their functions are influenced beneficially or harm- 

 fully, as the case may be, by their environment. They grow and 

 perform their duties properly when supplied with the needed pabu- 

 lum, but they are not immune to poisonous agents, and they are in- 

 jured when the products of their own activity accumulate about them. 



It is true, without exception so far as we know, that the excre- 

 tions of all living things, plants and animals, contain substances 

 which are poisonous to the organisms which excrete them. A man 

 may drink only chemically pure water, eat only that food which is 

 free from all adulterations, breathe nothing but the purest air, free 

 from all organic matter, both living and dead, and yet that man's 

 excretions would contain poisons. Where do these poisons originate ? 

 They are formed within the body. They originate in the metabolic 

 changes by which the complex organic molecule is split up into 

 simpler compounds. We may suppose — indeed we have good reason 

 for believing — ^that the proteid molecule has certain lines of cleavage 

 along which it breaks when certain forces are applied, and that the 

 resulting fragments have also certain lines of cleavage along which 

 they break under certain influences, and so on until the end products, 

 urea, ammonia, water, and carbon dioxid are reached; also that 

 some of these intermediate products are highly poisonous has been 

 positively demonstrated. The fact that the hydrocyanic acid mole- 

 cule is a frequent constituent of the leucomains, is one to which we 

 have already called attention. We know that chemical composition 

 is an indication of physiological action, and the intensely poisonous 

 character of some of the leucomains conforms to this fact. It matters 

 not whether the proteid molecule be broken up by organized ferments, 

 bacteria, or by the unorganized ferments of the digestive juices, by 

 the cells of the liver or by those still unknown agencies which induce 

 metabolic changes in all the tissues — in all cases poisons may be 

 formed. These poisons will differ in quantity and quality according to 

 the proteid which is acted upon and according to the force which acts. 



It is not our intention at this time to write extensively concerning 

 the autogenous diseases. We desire simply to call attention to the 



