In the same year, Griffith Evans discovered trypanosomes in a disease of horses and cattle in India, and the same type of parasite was found in the sleeping sickness.

Amoebae were demonstrated in one form of dysentery, and in other tropical diseases protozoa were discovered, so that we were really prepared for the announcement in 1905, by Schaudinn, of the discovery of a protozoan parasite in syphilis.

Just fifty years had passed since Pasteur had sent in his paper on "Lactic Acid Fermentation" to the Lille Scientific Society--half a century in which more had been done to determine the true nature of disease than in all the time that had passed since Hippocrates.

Celsus makes the oft-quoted remark that to determine the cause of a disease often leads to the remedy,( *) and it is the possibility of removing the cause that gives such importance to the new researches on disease.
(*) "Et causae quoque estimatio saepe morbum solvit," Celsus, Lib.

I, Prefatio .-- Ed.
INTERNAL SECRETIONS ONE of the greatest contributions of the nineteenth century to scientific medicine was the discovery of the internal secretions of organs.