FOOD OF WHALES. 169 



ing prey, and repeats the action till his vast stomach 

 is full, a great cauldron of living jelly. The jelly 

 soon disappears under the solvent action of the gastric 

 juice, and becomes the seething blood of the leviathan; 

 but the minute shells and frustules still travel un- 

 harmed ; the heat % the maceration, and the acid have 

 no power to dissolve them, and they at length come 

 forth from this ordeal as safe as from any former one. 



But it is probable that these siliceous and calcareous 

 atoms do not pass from the intestinal canal of the 

 Cetacea in individual isolation. They are individually 

 unchanged in form and structure, but are in all like- 

 lihood aggregated and conglomerated into cohering 

 masses, each mass homogeneous in its kind. Siliceous 

 particles, in particular, are known to have a power of 

 cohesion, with considerable tenacity under certain con- 

 ditions ; among which pressure, and an animal cement, 

 may be adduced. Professor Bailey, of New York, 

 found some masses of siliceous matter, obtained from 

 Diatomaceous deposits, which he in vain endeavoured 

 to break up by boiling in water and in acids, and by 

 repeated freezing and thawing. At length he boiled 

 the lumps in a strong solution of caustic alkali, under 

 which treatment they rapidly split up, and crumbled 

 to a paste composed of the frustules of Diatomcwece. 



Let us suppose, now, a school of whales rioting 

 amidst a vast field of Salpce, which, in their turn, 

 have been pasturing on microscopic Diatoms. Be 

 neath them, 



" A thousand fathoms down, " 



