Appamtus for preparing Muoric Ac'idj &c. 357 



xsaters of the southern, the Rio CunirV ana, Pai ime, ISIadari, 

 and Mao, pour themselves into the Ri\'eir Amazon. Some 

 desrees further towards the cast, tlie cordillera again extendi 

 in "breadth as it ascends southwards towards the Caniio Pa- 

 rara alono the Mao. It is here that the Dutch give to the 

 Cerro d'Ucuamo, the magnificent name of the Gol4- 

 Mountain, or Dorado, because it consists of a very shining 

 micaceous schistiis, a fossil which has brought into ce^brity 

 die small island of Vpamuccna in the lake of Padma. 



On the east from Rio F^squibo, or on the other side bf 

 the land of the Aturajo Indians the cordillera iivrns south- 

 east as it imites wil'h the garnet mountains of the Dutcli 

 And French Guiana, which are inhabited by a mixture of 

 NePToes and CariLs, and give an origin to the rivers Ee;- 

 hice, Surinam, Marony, Aprouaguc, and Oyapock. The 

 last mentioned ridge of mountains extends very much : its 

 gneis appears at Baxo Orinoco, in latitude 8° CO', between 

 the mouths of the Upata and A-cquire, and in latitude 

 Jt° 14' on the north side of the river Amazon, in the mou-.i- 

 tains of Fripoupon and Maya. 



Such is tiie form of the great cordilleras of the Cataracts, 

 which are inhabited by "a great number of uncivilized 

 savages, httle known to the Europeans. J must here ob- 

 serve, that in this description I have followed my own 

 observations only, and the notices we obtained from the 

 Indians, as also the observations of D. Antonio Santos, and 

 the companions of his journey, who <lictated to tKeir 

 friends. The maps of this part of tlie continent arc en- 

 tirely false, and the map added to the history of the Evir- 

 coco' bv P. Caulin, a work in other respects meritorious, is 

 by our last observations some di'grccs more \\ rong in longi- 

 tude and latitude than the map "published thlrt\- years be- 

 fore bv d'Anville. All the Indian names in it also are mu- 

 tilated', and mountains and rivers are delineated where none 

 <;xist ; a defect the more pardonable as the author was never 

 beyond the waterfalls of Orinoco, nor at the Rio Negro. 

 [To be continued.] 



LXV. DcuripfiMi of Mr. Richard Knight's Apparatus 

 for pri'parifig Fluoric Acid, and for Etching on Glass. 



J. I IF. fluoric acid, as every chemist knows, has the pro- 

 perly of dissolvino and volatilizing silex ; therefore vessels 

 jnad'e of glass, which consists clucfly of silex, cannot be 

 V:onvcnicntly cmploved to prcpltrt or retain this acid. The 

 Z :i luinmon 



