Licence: In copyright
Credit: On immunity with special reference to cell life / by Paul Ehrlich. Source: Wellcome Collection.
Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.
3/30
![Croonian Lecture.—On Immunity with Special Reference to Cell Life. By Professor Dr. Paul Ehrlich, Director of the Eoyal Prussian Institute of Experimental Therapeutics, Erankfort-on-the-Maine. Received March 17,—Read March 22, 1900. [Plates 6 and 7.] (Translation.) Honoured President, my lords and gentlemen,—It is to me the very greatest honour that I have been summoned here by your most highly esteemed Society, which for more than two centuries has represented and still represents the centre of the scientific life of England, in order that I may deliver the Croonian Lecture. I consider I am not so much personally concerned in the honour that you bestow on me, and that I shall not err if I see in it a recognition of the scientific path which I, in company with many others, have sought to follow, and which in your eyes suffices to place the field in which I work on a footing alongside of exact science. It is an extreme pleasure for me to have the privilege of addressing so many medical colleagues with whom for so many years I have been bound in close ties of friendship, and who have always been the first to welcome and to give recognition to the results of my work. Since Jenner made his great discovery of the protective action of vaccinia against small-pox, a century has passed away. During these years that terrible scourge of mankind has been almost completely eradicated from the civilised world. The beneficial consequences of Jenner's discovery are so evident to all who have any wish to properly appreciate them, that one wonders why, during so great a portion of the long period of 100 years, they were allowed to stand alone, with- out any endeavour being made to induce an artificial immunity in the case of other infectious diseases. This is all the more remarkable because Jenner's discovery demonstrated in their entirety those essential principles which, in later times, have been established for other infec- tious diseases. In the first place, it was shown that by the use of an attenuated virus, which of itself was non-injurious to the organism, it was possible to ward off the disease caused by the virulent virus. Jenner also established—what is most important from the practical point of view—that by the inoculation of the weakened poison there was produced not only an immediate, but also an enduring, protection. That Jenner's discovery remained so isolated was due' essentially to the fact that the theoretical conceptions of the cause and nature of infectious diseases made no advance during the sub- sequent decades; indeed, it would be an interesting topic for some historian of medicine to trace step by step the gradual advance in the b](https://iiif.wellcomecollection.org/image/b21951366_0005.jp2/full/800%2C/0/default.jpg)
