i^O Procefs for refolv'mg ^finerals hy Alkalies. 



2d, A fmall lamp capable of containing one ounce and ct 

 "half of fpirit of wine, furnifhed with a cover, a pair of fmall 

 tongs, and cotton to ferve as wicks. 



3d, A crucible capable of containing from two and a half 

 to tin-ee ounces of fluid, together with a fmall fpatula for ftir- 

 ring round the matter, both of the fined filver. 



The procefs of rcfolution is performed in the following 

 manner : — Put the foffil, reduced to a very fine powder, into 

 the crucible, and mix it with the ufual quantity of cauft'ic 

 alkali difiTulved in dillilled water; then light the lamp and 

 boil the whole, taking care to ftir it often round. As foon as 

 the mafs is dry, pour hot [diftilled] water over it ; then boil 

 it to drynefs again ; and repeat this procefs, Ihould the re- 

 iraftory nature of the foflil require it, for tv'o or three times 

 more, {till adding a like quantity of warm water. 



If large tough bubbles arife during the procefi of boiling, 

 it is in general a fign that the operation will be attended with 

 a good refult. 



I found the experiment fucceed in thrs manner with fe- 

 veral of the hardeft kind of foffils; fuch, for example, as the 

 Siberian beryl, quartz, fcld-fpar, the topaz, and even the 

 fapphire: the lart, however, was the nio(t refra6lory ; but it 

 was equally fo in the dry way, of w hich I have had an op- 

 portunity of being fully convinced. 



Argillaceous earth, and alfo the metallic oxyds, for ex- 

 ample thofe of titanium, tin, iron, &c. (which, as is well 

 known, lofe their property of being diflblved in acids, either 

 by too ftrong drying, or by too high a degree of oxydation), 

 by this eafy treatment, in ihe wet way, with cauftic alkali, 

 may be rendered again foluble, in the courfe of five mi- 

 nutes, merely by once boiling them to drynefs ; an efTecl 

 which, it was formerly believed, could not be produced but 

 by bringiiig them to a fiia^e of ignition with alkalies. 



The chief advantages of this new method of refolving foffils 

 in the wet way, are briefly as follow : 



id, The whole operation may be performed with the 

 greatefl: eafe and convenience on a table in any apartment, 

 even while rrading a book. 



ad, All the concomitating phenomena^ and thofe in par- 

 9 ticula? 



