INTRODUCTION AND SCOPE 5 



of purity, and here we are likely to learn more from colloidal than 

 from organic chemistry. Recent work on anaphylaxis seems to indicate 

 that this phenomenon is primarily concerned with a basic part of the 

 protein molecule which is resolved by hydrolysis into diamino-acids. 



We are almost as ignorant of the more interesting toxic products 

 of putrefaction as we are of pathogenic toxins. Very little is known 

 about the poisonous substances in food, popularly called ptomaines. 

 Many cases of so-called ptomaine poisoning are in reality bacterial 

 infections, but others are purely chemical intoxications. Perhaps the 

 best known of these is due to Bacillus botulinus which, without obvious 

 signs of putrefaction, produces in meat or even in vegetable nitrogenous 

 substances (beans) an excessively poisonous toxin, readily destroyed 

 at 80 and capable of yielding an antitoxin (Van Ermengem [1907, 

 1912; Ch. I]; Ornstein [1913; Ch. I]). The poisonous properties 

 occasionally exhibited by boiled mussels are on the other hand due to 

 a thermostable base [Brieger, 1886, I, p. 65 ; Ch. I]. The physi- 

 ological actions of the most active amines described in Chapter I do 

 not account satisfactorily for such intoxications ; other substances must 

 be present, and one of these is sepsine, a base of simple constitution 

 obtained by Faust from putrid yeast. The experimental difficulties 

 of the subject are illustrated by the fact that 100 kilos, of yeast did not 

 yield enough of the pure substance for quite satisfactory analysis. 

 Against this difficulty, that many of the bases described in the follow- 

 ing chapters are only obtainable in minute quantity from natural 

 sources, we may, however, set the advantage of a simple constitution, 

 so that when the latter has once been fully established, a synthesis on 

 a large scale may be possible, which in some cases has greatly increased 

 our knowledge of the chemical and physiological properties of the base. 

 Without an exact knowledge of the properties, the identification is 

 often very difficult and for this reason detailed descriptions have as far 

 as possible been given in the appendix. Many bases which have been 

 insufficiently characterised have not been mentioned, except where it 

 was possible to suggest identity with better known ones. 



In conclusion we may discuss the meaning of the following terms. 



Base. Many substances of physiological importance are at the 

 same time acids and bases ; those in which the basic character predomin- 

 ates have been included in this monograph ; others, like the tf-amino- 

 acids of protein are not generally regarded as bases, although glycine, for 

 instance, yields a hydrochloride. The predominance of the basic char- 

 acter may be deduced from a comparison of the (basic and acidic) affinity 

 constants (see the beginning of Chapter II). For our purposes a better 



