46 HISTORICAL SKETCH OF THE BACTERIAL POISONS. 



alkaloidal substance which was white, non-crystalline, unstable and 

 insoluble in water, but readily soluble in alcohol and ether. With 

 sulphuric acid and bichromate of potassium it yields a color reaction 

 very similar to that of strychnin. 



The action of the ether extracts from decomposed brain resembled 

 that of curare, but was less marked and more transitory. The 

 beats of the frog's heart were decreased in number and strengthened 

 in force ; the nerves and muscles lost their irritability, and the ani- 

 mal passed into a condition of complete torpor. The pupils were 

 dilated. Guareschi and Mosso, using the Stas-Otto method, obtained 

 from human brains which had been allowed to decompose at a tem- 

 perature of from 10° to 15° for from one to two months, both vola- 

 tile and non- volatile bases. Among the former only ammonia and 

 trimethylamin were in suflBcient quantity for identification. With 

 these, however, were minute traces of ptomains. They obtained 

 non-volatile bases from both acid and alkaline solutions. From the 

 former they separated a substance which gave precipitates with 

 gold chlorid, phosphotungstic acid, phosphomolybdic acid, Mayer's 

 reagent, palladium chlorid, picric acid, iodin in potassium iodid, and 

 a slight one with tannic acid. This substance was not precipitated 

 with platinum or mercury. 



From the alkaline extract there was obtained a substance which in 

 dilute hydrochloric acid solutions gave with gold chlorid a heavy 

 yellow precipitate with reduction, also precipitates with phospho- 

 molybdic acid, platinum chlorid, Mayer's reagent, picric acid, phos- 

 photungstic acid, Marm6's reagent, iodin in potassium iodid, tannin, 

 bichromate of potassium, palladium chlorid and mercuric chlorid. 

 It reduced ferric salts. From decomposed fibrin the same investi- 

 gators obtained one well-defined ptomal'n. Analyses of the platinum 

 compound of this substance gave the formula Cj^Hj^N. This body 

 will be discussed in a future chapter. 



From fresh brain substance they separated ammonia, trimethyl- 

 amin, and an undetermined base. These, however, are not to be 

 regarded as products of putrefaction, but as resulting from the 

 action of reagents upon the brain substance. The trimethylamin 

 probably arises from the splitting up of lecithin, while the undeter- 

 mined base is most likely cholin, which also results from the break- 

 ing up of the lecithin molecule. 



They also show that when Dragendorff's method is used basic sub- 

 stances can be obtained from fresh meat, and these are shown to be 

 produced by the action of sulphuric acid on the flesh. 



In 1885, Vaughan detected in poisonous cheese an active agent to 

 which he gave the name " tyrotoxicon," and this discovery has been 

 confirmed by Newton, Wallace, Schaeffer, Stanton, Firth, Ladd,WolfiF, 

 Kimura, Davis, Kinnicut, and others ; however, as we shall see later, 

 this is not the substance most commonly found in harmful cheese. 



