Page:The advancement of science by experimental research - the Harveian oration, delivered at the Royal College of Physicians, June 27th, 1883 (IA b24869958).pdf/48

 with interest, and especially in connection with a disease of so frequent occurrence as phthisis. The phenomena of tubercle since the time of Laennec and Carswell, have been wonderfully cleared up. There was truth in the views of Dr. Williams, who referred tubercle “to a degraded condition of the nutritive material,” and that in its origin it differs” not in kind, but in degree of vitality and capacity of organisation. The clinical observations of Dr. Addison rested on a sound basis, when he declared that inflammatory changes were of the greatest importance in the pathology of the disease. The microscopical observations of Gulliver have been advanced by W. Addison, Virchow, Langhans, Rindfleisch and many others; but perhaps the most interesting observations have been those of Villemin.

He shews, that animals inoculated with fresh tubercle become tuberculous; tubercles were found in the spleen, in the lungs and in other viscera; from his experiments it was supposed that there was a special virus which would reproduce the