64 VIEWS OF THE MICROSCOPIC WORLD. 



A question naturally arises, what are the ends which these Infusorial atoms 

 subserve when living, whose remains form, either partially, or wholly, such ex- 

 tensive portions of the surface of the earth ? To them have been attributed malig- 

 nant influences ; for the various epidemics, which at intervals have swept down our 

 race, have been supposed, by some, to originate in a " living cloud '' of existences, 

 dwelling in the air. But of this we know nothing certain, and a more satisfac- 

 tory answer cannot be given than that which is contained in the words of Professor 

 Owen, who thus unfolded his views upon this subject, in one of his lectures : 

 " Consider their incredible numbers, their universal distribution, their insatiable 

 voracity, and that it is the particles of decaying vegetable and animal bodies 

 which they are appointed to devour and assimilate. Surely we must, in some 

 degree, be indebted to these ever active, invisible scavengers for the salubrity of 

 the atmosphere, and the purity of water. Nor is this all, they perform a still more 

 important office in preventing the gradual diminution of the present amount of 

 organized matter upon the earth. For when this matter is dissolved or sus- 

 pended in water, in that state of comminution and decay, which immediately 

 precedes its final decomposition into the elementary gases, and its consequent 

 return from the organic to the inorganic world ; these wakeful members of 

 nature's invisible police are everywhere ready to arrest the fugitive organized 

 particles, and turn them back into the ascending stream of animal life. Having 

 converted the dead and decomposing particles into their own living tissues, they, 

 themselves, become the food of larger Infusoria, and of numerous other small 

 animals, which in their turn are devoured by larger animals : and thus a food, 

 fit for the nourishment of the highest organized beings, is brought back, 

 by a short route, from the extremity of the realms of organized matter. 

 These invisible animalcules may be compared, in the great organic world, to the 

 minute capillaries in the microcosm of the animal body ; receiving organic matter 

 in its state of minutest subdivision, and when in full career to escape from the 

 organic system, and turning it back, by a new route, towards the central and 

 highest point of that system." 



