INTROD UCTION. 1 1 



basic nature* Such bodies were first found by SELMI in human 

 cadavers, and called by him cadaver alkaloids or ptomaines. These 

 ptomaines, which have been studied by a great number of investi- 

 gators, especially by SELMI, BEIEGER, and GAUTIEE, must be con- 

 sidered as products of chemical processes caused by putrefaction 

 microbes. Some of these ptomaines are exceedingly poisonous, and 

 consequently BRIEGER has called them toxines. 



The formation of such poisonous products in the decompositions 

 caused by putrefactive microbes makes it probable that the lower 

 organisms acting in infectious diseases also produce poisonous sub- 

 stances which may cause by their action the symptoms or compli- 

 cations of the disease. BRIEGER, who has become prominent by 

 his study of this subject, has been able to isolate from typhus 

 cultures a substance called typhotoxin which has a poisonous action 

 on animals; and he has also prepared another substance, tetanin, 

 from the amputated arm of a patient with tetanus, animals- inocu- 

 lated with which die exhibiting symptoms of developed tetanus. 

 Admitting that the results obtained thus far upon this subject are 

 not very numerous, we cannot refrain from stating that the facts al- 

 ready found open a promising field for further labor and research. 



As above stated, the chemical processes in animals and plants do 

 not stand in opposition to each other; they offer differences indeed, 

 but still they are of the same kind from a qualitative standpoint. 



PFLUGER says that there exists a blood-relationship between all 

 living cells of the animal and vegetable kingdoms, and that they 

 originate from the same root ; and if the organisms consisting of one 

 cell can decompose protein substances in such a manner as to pro- 

 duce poisonous substances, why should not the animal body, which 

 is only a collection of cells, be able to produce under physiological 

 conditions similar poisonous substances ? The poisonous secretions 

 of toads, serpents, and numerous other animals prove, in fact, that 

 the animal body has this power. Frequent efforts have been made 

 of late to prove that the human organism under physiological con- 

 ditions produces poisonous substances. In the human saliva (GAU- 

 TIER and others), and especially in the urine (POUCHET, BOUCHARD, 

 and others), but also in the expired air (BROWN-SEQUARD and 

 D'ARSONVAL), poisonous organic substances have been proved to 

 exist. The correctness of many of these statements is contradicted 



