'^tial^s of Manachantte from 'Botany Bay. 133 



fufion, the mafs became brownifh, and quickly changed to a rich emerald green. After 

 keeping it red hot for half an hour, the crucible was withdrawn from the fire, and the mafs 

 diluted in water. The liquor, npt without fediment, was of a very beautiful green, as is 

 ufual in fofTiIs, where iron is abundantj arid but little oxidated. 



2. Muriatic acid was then poured in, and a total folution enfued. This liquor was fet 

 on a fand heat to evaporate at a moderately elevated temperature. After fome time, a white 

 matter, much like curdled miJk, began to appear, and afterward increafed to a confiderable 

 volume. This fubftance, feparated by filtration, was well wafhed, and the liquor agaia 

 expofed to the fame temperature was evaporated to drynefs. 



3. Upon pouring in a large quantity of diftilled water to re-diflblve the mafs, a precipi-- 

 taie, which was filica, remained behind; but the liquor pafled very turbid through the 

 filtre, although repeated attempts were made to render it limpid by that method. 



4. A folution of pot-a(h was poured in excefs into this turbid liquor, a red and confi- 

 derable precipitate fell to the bottom. The whole was made to boll ; but no diminutiott: 

 took place in the apparent volume of the precipitate. The liquor was filtered, and eflayed 

 for alumina; but the pot-afli did not appear to have diflblved any thing. 



5. The red precipitate was again diflblved in muriatic acid, and elTayed by the knowa^ 

 ire-agents, for the different earths and metals. From thefe trials it appeared to be oxide of 

 iron, mixed with a fmall portion of the fame fubftance as that which had coagulated in the 

 firft attempt to evaporate the intire folution, as above flated. 



6. I now proceeded to examine the nature of the white fubftance (Exp. 2d.) which had 

 feparated' itfelf by fpontaneous precipitation. I attempted to re-diflblve a portion of it in 

 muriatic acid, but could not fucceed. Nitric acid was much more effe£lual ;. but fulphuric 

 acid) after being gently heated with i\f operated a perfeft folution. Spme trials, made 

 with the different re-agents upon the latter folution, aflbrded the following refuTts : 



With pot-alh, foda, and ammonia, a white precipitate ; with carbonates of pot-a(h, of; 

 foda, and of ammonia, ditto; with a muriate or a nitrate^ no precipitate ; with an oxa- 

 late, a white precipitate; with a tartrite, a white precipitate ; with a phofphate, a copious 

 white precipitate; with an arfeniate, a ditto ditto; with fulphurated hydrogen water, no 

 precipitate; with an alkaline hydro-fulphuret, a dirty glafs green precipitate; with a 

 prufliate, a dark blueifli green, which (hewed that there was ftill fome iron ; with tindture 

 of galls, a blood red, and very thick precipitate; with phofphoric acid, a white precipi- 

 tate ; with arfenic acid, a white precipitate. 



Thefe eXfperiments,. and particularly the laft three,, were fufiiciently chara£leriftic, and, 

 proved that this fubftance could be. no other ^han oxide of titanium. However, it was 

 ftill contaminated with iron ; and a part of it appeared to have remained with that red pre- 

 cipitate, which ^as already mentioned.. To effe^ a complete feparation was ftill a defide- 

 ratum. For this purpofe, I repeated the experinients upon different portions of the fand. 

 After fufion with pot-afh, and folution in muriatic acid, I attempted to precipitate the 

 whole, and then to difTolve in an excefs of carbona:te of ammonia, the oxide of iron, become 

 3 Kdi 



