142 GLIMPSES OF NATURE. 



science. These germs of disease, dispersed broadcast, 

 like the germs of the yeast-plants and of the blue 

 moulds, seek a soil in the shape of the animal frame. 

 Once found, this soil is utilised, and there is witnessed 

 in the case of the body an analogous process to that 

 seen in the wine. The little leaven (of disease) which 

 leavens the whole lump (of the body) is exactly repre- 

 sented by the fever-germ. With the Apostle, one 

 might go further and assert that, sown in weakness, 

 the germ appears in strength. In each case the little 

 living particle, whether of the mould, the yeast-plant, 

 or the fever, reproduces its like. It multiplies ex- 

 ceedingly; the few germs become thousands, and all we 

 see happening, alike in fermentation and in the fever, 

 is merely the result of germ-growth. " Like begets 

 like," and thus the germ reproduces in each case, some- 

 times directly, sometimes indirectly, the likeness of the 

 parent to which it owed its origin. 



Questions of size are always difficult to settle or 

 determine from a popular point of view, and, when we 

 seek to gain some adequate idea of the dimensions of 

 germs, we are met with the difficulty of translating 

 into terms of common life those of the infinitely little. 

 If we speak of a germ which in length is the one ten- 

 thousandth part of an inch that is, equals one part 

 of an inch which has been divided, as to its length, 

 into ten thousand parts- we utterly fail to grasp any 

 notion of the size indicated. An appeal to figurative 

 description, while more graphic in character perchance, 

 yet leaves us with the dimmest conceptions of the 

 dimensions of germs. 



One writer tells us that on the area of a single 

 square inch we could place, in a single layer, a popu- 

 lation of common germs or bacteria, one hundred times 



