which however appears also in the first grand division) they are 

 distinguished from the metallic minerals, or ores properly so call- 

 ed, by their solubility in water, and from earthy salts in general, 

 by the styptic metallic flavor which they impart to the palate. 

 They are, obviously, too few to require division, being readily 

 distinguished from one another by their chemical characters. 



Appendix. 



All those metallic minerals, whose characters are not sufficient- 

 ly known to admit of being introduced with confidence into one 

 of the foregoing tables are entered here. 



General Observations upon these Tables. 



The object held constantly in view, in forming these tables, has 

 been to prevent, as far as the compiler has found it possible to do 

 so, the individual who may consult them, from^experiencing dis- 

 appointment. To effect which the former has found it necessary, 

 in consequence of the sometimes doubtful or contradictory infor- 

 mation which the systems of mineralogy* consulted, afford, to re- 



• The individual who shall study the different systems in Mineralogy which are 

 extant, even in his own language, will be struck, occasionally, by the contradictions 

 which occur in the descriptions given of the same mineral by contemporary writers, 

 and every successor flatters himself that he has corrected the apparent errors oi his 

 predecessor. I say apparent because there is full as much reason to suppose that 

 the difference in descriptions arises out of a real difference in the specimens examin- 

 ed, as that any error exists in the observations of distinguished mineralogists, and 

 indeed these very contradictions are often a proof that such are not the labors of a 

 mere compiler like myself With this impression we thought it advisable to make these 

 tables embrace all discrepances met with in the works consulted. There is less risk of 

 error by adopting this plan, than in neglecting it, for should it ever happen, as is possible 

 that a given mineral will in consequence sometimes be out of its place, it will be 

 associated with others, the difference in whose characters, will sufficiently distin- 

 guish them. The necessity of adopting a similar arrangement as regards the fusi- 

 bility or infusibility of minerals, is very apparent ; because it cannot be supposed 

 that all operators with the blow-pipe will produce the same effect on the same min- 

 eral. It is easy to conceive, for instance, that Berzelius would in some instances, 

 describe that body as fusible, which another, less practised than himself, would con- 

 sider infusible. A difference in the results also arises from the form and size of 

 the assay, and from the kind of blow-pipe made use of, particularly as regards the 

 size of its bore. These considerations have induced the compiler to insert under the 

 grand division of infusible, even those minerals which are described as difficultly or 

 only partially fusible, and vice versa. 



