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rapidly-proliferating cells I must not enter. This process of genuine suppuration of the blood-clot removed all the difficulties I had felt in interpreting the post-mortem appearances in pyaemia, and also its clinical features.
Having become familiar with the appearances of these cells in suppurating coagula, I was able to recognise them in acute abscesses in the human subject, and to demonstrate them to others by mixing carmine with the pus, so as to render clearly defined the limits of the pellucid bodies of the cells, which otherwise would have been regarded as liquor puris.
I am, of course, aware of the great importance of the emigration of leucocytes, discovered by Cohnheim, and rendered immeasurably more interesting by Metchnikoff's observation of their phagocytic powers; and I know that collections of pus have often such an origin. But I am quite satisfied that this is not the exclusive mode of pus formation, and that it is often produced by the proliferation of cells, as was first taught by my illustrious predecessor in this chair of two, years ago (Professor Virchow), in the "Cellular Pathologie."
While these investigations into the nature of pyaemia were proceeding, I was doing my utmost against that deadly scourge. Professor Polli, of Milan, having recommended the internal administration of sulphite of potash on account of its anti-putrescent properties, I gave that drug a very full trial as a prophylactic. I have notes of a case in 1864, in
