There is no doubt that the tubercle bacillus can be conveyed to the human subject by milk from tuberculous cows, and that children have been infected in this way and have lost their lives. It is therefore a wise precaution to boil the milk taken by children; indeed, when the source from which it is obtained is not known it is absolutely necessary to do so.

That consumption can be caught by the healthy from a consumptive patient is now a well-authenticated fact. The tubercle bacilli abound in the expectorations of the consumptive, which should not, therefore, be spit on to the floor or ground and left to dry, for in this way the bacilli are disseminated in the atmosphere, and if then inspired into the lungs may induce consumption in the nurse or attendant. Hence it is of the utmost importance that the expectorations of consumptives should be spit into covered vessels, that they should be carefully collected and burnt, and that similar precautions should be taken in the home and in the sleeping apartment. A healthy person should never sleep in the same bed with a consumptive.

Fig. 11. - The Tubercle Bacillus, Magnified 1000 Times.