248 Procefs for refolving Minerals ly Alkalies. 



wards, in the examination of other minerals, that our ope- 

 rations {hou!d be miihiplied. As this occafions a great con-r 

 fumption of time, it may at length happen that the chemift, 

 in the whole courfe of his life, efpecially as human life is fo 

 (hort in general, would not be able to examine, with the re- 

 quifite accuracy and patience, but a very fmall number of 

 minerals. The worlt confequence of this would undoubtedly 

 be, that ouf progrefs in the iludy of nature would be mucli 

 retarded. 



This inconvenievce, however, might be remedied, if che- 

 mifts in their refearches would endeavour to fliorten and Am- 

 plify their operations as much as polfible; and, when they 

 difcover eaficr and fliorter proceffes, if they would make them 

 known in a chemical journal, which might be entitled, Col- 

 leftions towards facilitating Chemical Decompofitions. After 

 this fliort digreffion, I fliall now proceed to the main object 

 of this paper, which, 1 hope, will be confidered a contribu- 

 tion towards a work of the above kind, not unimportant, and 

 which may be thought worthy of fome attention. 



It is well known that moft foffils, particularly thofe of the 

 earthy or filiceous kind, to be rendered foluble by acids, and 

 confequently fit fur being analyfed, require a preparation 

 with fixed alkalies; an operation which is called rejolullon. 



It has hitherto been believed that this refolution could be 

 efl'e(5lcd only by reducing the foffil to an exceedingly fine 

 powder, mixing It with alkaline falts, and then keeping it 

 for feveral hours in a (late of ignition. Formcrlv, the alka- 

 line carbonats were made choice of for this purpofe, till pro- 

 feflur Klaprf>lh, foine years ago, iLowed that the pure op 

 cauflic alkalies were preferable. This meritoiious chemift, 

 who has contributed fo much to the improvement of our 

 chemical knowledge, recommends that the follil, finely 

 pounded, fliould be firft boiled to drvncfs with cauftic alkali, 

 and that the dry mafs (Iiould then be kept at a red heat for 

 feveral liours in a iilver crucible, taking care, however, not 

 to melt the crucible. This method has hitherto been con- 

 fidered, both by niyfclf and bv oilier cheuiifls, as the heft, 

 atid on that account has been followed. 



For 



