Since 1919, when Sazerac and Levaditi1 published their researches on the antisyphilitic effect of bismuth compounds, there have been many contributions on the spirocheticidal value of this product. The strange thing is that while bismuth is known to possess considerable curative power both in experimental rabbit syphilis and human syphilis, and a feeble effect in trypanosome infections, it was on the basis of its trypanocidal properties that the drug was first introduced into medicine. The discoverers of these trypanocidal effects were Robert and Sauton.2 Our own study of the value of bismuth compounds in trypanosomiasis caused by Trypanosoma equiperdum shows that bismuth possesses practically no curative power.
A study of Table 1 demonstrates that potassium bismuth tartrate in as high a dose as 0.015 per kilogram failed to diminish the number of trypanosomes in the blood, the animal having died from infection on the sixth day. Arsphenamin, in