304 



Analysis of 

 the tvsuer. 



STATURAL HISTORY OF JATA, &C. 



[533 yds} across the widest part of its bottom. Here he 

 pereeived four openings, or mouths, near the top of the 

 cavity, continually emitting clouds of sulphurous acid 

 yapour, which, being condensed by the action of the cold 

 air, fell into a great lake at the bottom, which is contained 

 in the crater of the ancient volcano. 



The waters in this basin, thus continually impregnated 

 with the vapour, become so acid, that they attack every 

 thing they touch ; altering all the adjaeent lava, and form- 

 ing sulphate of iron and of lime, which they hold in solu- 

 tion, as well a.-, sulphate of alumine. Accordingly when the 

 rainy season arrives, the lake swells, overflows, and conta- 

 minates the water of the White river. 



The cause being thus known, it is easy to obviate the 

 noxious mixture of this water, by turning aside that which 

 descends from the lake at certain seasons ; and opposing 

 obstacles sufficient to prevent its reaching the White river, 

 which would thus remain constantly wholesome. This is a 

 service of no small importance to the colony. 



Mr. Vauquelin has analysed the acid water of this lake, 

 and found ia it sulphuric acid, sulphurous acid, muriatic 

 acid, sulphur, sulphate of potash, alum, and 6ulphateof iron. 



Meadow iron 

 ore. 



Granular iron 

 •re. 



XIII. 



Analyses of Minerals: by Martin Henry Klaprotii, 



Ph. D. $c. 



{Continued from p. \6\J. 



1ESENERZ (meadow iron ore). 



Black oxide of iron 66 



Oxide of manganese 15 



Phosphoric acid • 8 



W 7 ater 23 



98-5 

 Pisiform ironstone from Hogau. 



Osule of iron -...•53 



Silex 23 



Alumine • • 6'5 



Oxide of manganese t 



Water « 14*5 



08 Granular 



