Page:The Harveian oration 1888.djvu/26

some chemical poison developed in putrefying material. He subjected the fluids to prolonged boiling so as to destroy any living organisms, and on injecting it into animals the poisonous effects were still produced though in a slighter form than from the unboiled fluid. Further, after filtering the fluid and boiling it for an hour he evaporated it to dryness, then digested it with absolute alcohol and treated the residue with boiling water. This watery extract also was poisonous. Some of these chemical substances or animal alkaloids were separated by Armand Gautier in 1872 and by Professor Selmi of Bologna and named by him ptomaïnes. Professor Brieger has since succeeded in producing these bodies, and some not poisonous, in a crystalline form, and in determining their chemical composition. The following are some of them:

Neuridin C₅H₁₄N₂, a non-poisonous alkaloid, is the one which is most constantly present at the commencement of putrefaction and which appears in largest quantity. This substance can be split up into dimethylamine and trimethylamine:—

After the removal of this from putrefying flesh two poisons can be extracted, neurin C₅H₁₃NO and cholin C₅H₁₅NO₂, differing only in composition by a molecule of H₂O, but the neurin being ten times more poisonous than cholin; which latter exists normally in the bile, and as a constituent of lecithin in the brain, and in yolk of egg. From putrefying fish, and gelatine, muscarine C₅H₁₅NO₃ is obtained; an alkaloid previously discovered by Schmiedeberg and Koppe, as the poisonous agent in a disease of flies caused by a fungus, the agaricus muscarius. Brieger also obtained other substances from decomposing albuminous substances and human corpses, viz. ethylene diamine C₂H₄(NH₂)₂, gadinin C₇H₁₇NO₂,