…By isolating the components sought.

“A very simple incident had the momentous consequence of fulfilling our efforts and interests, for we were appointed to form part of an official Commission that, in Spain, had been entrusted with studying and clinically testing Salvarsan, better know and made popular by its numerical name: 606.

The Commission acted seriously and conscientiously on abundant, well-selected clinical material, generously provided with phials of Salvarsan and also using what was then extremely modern means of research, which consisted of testing the Treponemas under the ultramicroscope and the practice of the Wassermann reaction”.