Z YMO TIC DISEASE. 8 9 



It would be too much to say that this frightful 

 mortality represents the deaths from preventible 

 diseases, but there can be little doubt that good sani- 

 tary regulations, combined with cleanliness and tem- 

 perance upon the part of the people, would save at 

 least 100,000 lives annually in England and Wales 

 alone. But this eminently practical part of the sub- 

 ject has been well considered by others far better 

 qualified for the task than myself. I therefore pass 

 on to discuss the nature of the material concerned in 

 the spread of contagious diseases. It was shown in 

 the first part of this work that the active substance 

 was not a lowly vegetable organism developed 

 independently of man or the animals subject to 

 disease. We have, therefore, now to enquire what is 

 the material substance which passes from the diseased 

 to the healthy organism in small-pox, in measles, in 

 scarlet fever, and other allied contagious diseases 

 from which man and domestic animals suffer so 

 severely. The material in question grows and multi- 

 plies and produces its kind as all living things do, 

 and as nothing that does not live has been proved to 

 be capable of doing. We may therefore conclude that 

 it is living matter. But it has been already shown 

 that it is not a vegetable organism. What then is its 

 nature ? The arguments advanced against a vegetable 

 germ theory of disease do not perhaps apply to some 

 other forms of a germ theory, one of which will be 

 considered. 



