(_b_) Persons bitten by dogs declared to be mad by competent veterinary surgeons. (_c_) All other cases. The mortality even in Class A is very slight, though many patients are not brought until late. Incidentally it may be remarked the lesson of this country in its treatment of hydrophobia is one of the most important ever presented in connection with an infectious disease. There are no Pasteur Institutes; there are no cases. Why? The simple muzzling order has prevented the transmission of the disease from dog to dog, and once exterminated in the dog, the possibility of the infection in man had gone. In 1888 the crowning work of Pasteur’s life was the establishment of an Institute to serve as a centre of study on contagious disease, and a dispensary for the treatment of hydrophobia, which is to-day the most important single centre of research in the world. The closing years of his life were full of interest in the work of his colleagues and assistants, and he had the great satisfaction of participating, with his assistant Roux, in another great victory over the dread scourge, diphtheria. Before his death in 1895 he had seen his work prosper in a way never before granted to any great discoverer. To no one man has it ever been given to accomplish work of such great importance for the well-being of humanity. As Paul Bert expressed it in the report to the French Government, Pasteur’s work constitutes three great discoveries, which may be thus formulated. 1. Each fermentation is produced by the development of a special microbe. 2. Each infectious disease is produced by the development within the organism of a special microbe. 3. The microbe of an infectious disease culture, under certain detrimental condition is attenuated in its pathogenic activity; from a virus it has become a vaccine.