S94 Introduction to the Study of Mineralogy. 



have said, upon the existence of a principle common to the 

 different kinds, the distinction of which afterwards bears 

 upon the principles which are peculiar to them. 



We see from what precedes, that chemistry and mine- 

 ralogy necessarily concur to the formation of a method, 

 whatever it may be, which has for its object the classifica- 

 tion of inorganic bodies ; that it belongs to chemistry to lay 

 the first foundations of the method by the determination of 

 the species ; and that the difference depends upon what is 

 contributed by each to the construction of the edifice which 

 is raised upon that basis. I shall soon detail the principles 

 which seem to me to conduce to the most advantageous ap- 

 plication of this kind of alliance. 



On the other hand, natural philosophy unites with che- 

 mistry in order to furnish mineralogy with distinctive cha- 

 racters, the more advantageous from their diving to the very 

 bottom of substances, and they are much less variable than 

 those of which we judge only with respect to the manner in 

 which they strike our senses. Experiments equally simple 

 and easy seem to give us new organs, in order to penetrate 

 to the most intimate properties of a substance : and we may 

 answer those who think that mineralogy is sufficient for its 

 own wants, without intermixing with foreign substances, 

 that in operations so elementary, and requiring so small an 

 expense, we see neither the naturalist nor the chemist pro- 

 perly so called, but the mineralogist alone, interrogating 

 nature in a more urgent and more fortunate manner*.. 



Geometry, in its turn, has direct and necessary relations 

 with mineralogy, by the description of crystalline forms, 

 and still more by its numerous applications to the structure 

 of crystals, which, of itself, is only the result of a natural 



* Although this simple indication of chemical and physical properties be 

 sufficient for fulfilling our principal object, wc have thought it right to add 

 the explanation of these properties, and thus to labour for men more particu- 

 larly versant in the sciences by which mineralogy may be extricated from the 

 Jabyrinth of phrases purely descriptive, and be raised to the rink of the true 

 sciences, which aggrandize their object by ascending to the laws to which 

 thev are subjected. They will of course do us a service, if they do not con- 

 fine us to the results of solitary experiments, but, on the contrary, proceed 

 to show their connection with the causes upon which they depend. 



geometry, 



