344 POPULAR SCIENCE MONTHLY. 



No tuberculosis liad ever been known in any of the families, ex- 

 cept perhaps in the case of one grandmother, who had marks of 

 former abscesses in her neck. A and his wife lived on dry soil. 

 They had nine children, all of whom remained healthy. The 

 house of B, on the other hand, was on damp soil. His wife and 

 six of his eleven children died of consumption, and one of the sur- 

 vivors was ill with the disease when the observations were made. 

 The importance of these predisposing conditions can only be 

 realized by knowing that the large majority of consumptives have 

 never lived with others similarly affected. The disease is in these 

 cases a result of a combination of circumstances into which direct 

 known exposure has not entered. Nor can immunity be secured 

 by shunning the sick. In fact, nothing further is required to 

 protect those of sound health and heredity, who are obliged to 

 associate with consumptives, than scrupulous cleanliness and an 

 abundant supply of fresh air and sunshine. If, in addition, the 

 sputum and everything soiled by it are destroyed and disinfected, 

 the sick become harmless to all. The human body has within it 

 the capacity of preventing the lodgment and growth of the tuber- 

 cle bacillus. This capacity is only overcome as a result of heredi- 

 tary or acquired influences. It is against these that the efforts of 

 every one can and ought to be directed. 



DISINFECTION AT QUARANTINE. 



A FLOATING DISINFECTING PLANT. 



By M. E. ward. 



THE necessity of thorough precautionary quarantine methods 

 is generally accepted. The adoption and adaptation of 

 methods and apparatus to keep pace with the knowledge that 

 scientific research has placed at command is a matter that directly 

 concerns the public and the departments of public health. That 

 ceaseless watchfulness should be maintained, that trained dili- 

 gence combined with high scientific skill should be a means to 

 attain efficiency, that appliances in use should combine simplicity 

 with efficiency, that in their operation delay of all kinds should 

 be avoided, and that the individual should receive consideration 

 and every comfort and convenience enlightened civilization can 

 provide, are axiomatic facts. 



Our great seaports and ports of entry are the centers most ex- 

 posed to contagion and infection. Disease germs from the civ- 

 ilized and uncivilized parts of the world tend to drift there, car- 

 ried by an ever-moving stream of emigration and traffic. The 

 larger the center, the greater the number that pass through it to 



