With Pasteur's discovery of the micro-organic world civilization entered upon a new epoch. With it many of the phenomena of life which had not been understood and which had led to superstitious practices became clear and intelligible. Disease for the first time appeared in its real character and came within the control of man on a rational and exact basis. In the wake of Pasteur's work Koch discovered the active cause of consumption, a living entity subject to the same fundamental laws as govern all living things. With Koch's revelation an onslaught upon consumption began. It has gained force with every step since then and will culminate in the complete extermination of the white plague, as consumption has been properly termed.