342 INDEX. 



Northweft, or Northeaft paffage to China ; of its exiltence, i. 



144. 

 Nutrition and growth- of animals ; diiTertation on it, ii. 39. 



Ocean kept in perpetual motion fince the beginning of time, i. 7. 

 17. Its bottom as irregular as the furface of the dry land, 

 7. Mountains, currents, calms, &c. in different parts of the 

 ocean, 8. Different kinds of plants and animals found in it, 

 9. Its waters muft have remained for a great number of 

 years en the earth, 1 1. Flux and reflux of the ocean are the 

 caufes of the horizontal pofition of the ftrata of the earth, i?. 

 . Waters of the ocean have a cpnftant motion from eaft to weft, 

 31.32. May again cover the earth, 41. General account 

 of the changes produced by its fiui and reflux, 57. The 

 faltnefs of the ocean proceeds from banks of fait in its bottom, 

 and likewife from the falts brought down by rivers, 275. Its 

 water excefiively cold at great depths, ib. Is not more fait at 

 the bottom than at the furface, 276. fulphureous fprings, 

 beds of bitumen, &:c. found at the bottom of the fea, 276. 



Ocelot, or Mexican cat defcribed, vii. 243. The moft beautifnl 

 of all fpottsd animals, 245. Is exceffively fond of blood, 

 246. Cannot be tamed, 247. 



Odobenus, vii. 355. n. 



Old age ; a differtation upon it, ii. 470.' 



Olive cavy. See Akauchi. 



Onager, vi. 264. n. 



OpoflTum, V. 405. n. 



Opoffum of Virginia defcribed, v. 404. Has a cavity under the 

 belly, in which the young are received and fuckled, ih. The 

 fame with the great oriental philander of Seba, 407. Re- 

 marks on his account of thefe animals, 411. The opolTum 

 is an original native of the vrarm countries of America, 422. 

 Its time of geftaticn probably much Ihorter than that of other 

 qnadrupeds,423. Its pouch not to be regarded as indifpea- 

 fibly neceffary for the prefervation of the young, 424. The 

 young opoffums never quit the teats with their mouths till 

 they have ftrength to walk, 425. Manner of the opoffumfs 

 catching its prey, 42 7. Is eafily tamed, but has a difagreeable 



appearance 



