By means of a combination of the microscope with the camera, this picture depicts the course of this virulent fever. In Russia, which has at times been visited by terrible epidemics of recurrent fever, the disease is caused by the bite of a flea that carries the disease, while in Africa it is the tick found in that country that transmits the disease. The picture is illustrated with observations of the blood of a monkey that has been inoculated. The germ soon multiplies, and innumerable bacilli can be discerned in a single drop of blood under the microscope. The sickness comes in spells, between which the germ disappears and the animal seems cured, but the germ soon appears again in great numbers and after several attacks the patient is lucky if it escapes from death.
