236 PICTURESQUE SKETCHES 



" And it is not difficult to understand in what way 

 this result is produced, for, when the organic matter 

 is in that state of comminution and decay which im- 

 mediately precedes its return from the organic to the 

 inorganic world, these wakeful members of nature's 

 invisible police are everywhere ready to arrest the 

 fugitive particles, and turn them back into the ascend- 

 ing stream of animal life. Becoming the food of the 

 smaller infusorial animalcules, they again supply the 

 voracity of the larger ones, and of numerous other 

 small animals, which in their turn are devoured by 

 larger ones, and so, by degrees, the substance fit for 

 the nourishment of the most highly organized classes 

 is brought back by a short route from the extremity 

 of the realms of organized matter." 



It is a remarkable and very interesting fact with 

 regard to these animalcules, that their light, though 

 siliceous skeletons, are capable of being transported 

 by the air in the form of fine dust to the distance of 

 many hundred miles out at sea ; and the quantity so 

 transported is often sufficient to cloud the air, and 

 form a sensible deposit on the decks and rigging of 

 ships. The microscope alone is capable of proving 

 whence this dust comes, but, with its aid, they can 

 be recognized, identified, and traced to that conti- 

 nent or island, which is not always the one nearest 

 at hand, where they are indigenous. It will not 

 be surprising, also, since we thus find the bodies 

 of the animalcules themselves carried along by mil- 

 lions through the air, that their eggs may be carried 

 yet farther, and prove a bond of union between dis- 

 tant lands, whose other inhabitants have no relation. 

 Who could have imagined that the atmosphere is in 



