THE DEVELOPMENT OF MINERALS. 403 



of elasticity, null in some directions ; variation in the mutual inclina- 

 tion of the facets ; in the same system, a transition from hemihedral 

 to holohedral forms by sharp grouping in some cases, by striae like 

 those of pyrites and quartz, of holohedral forms to forms hemitropal 

 in different degrees, and to hemimorphal forms. The complication 

 goes on increasing. 



We will end by a last trait of analogy. Just as some animals and 

 plants, when they are by any cause placed in a medium offering the 

 largest sum of propitious conditions, attest the excellence of that me- 

 dium by a more complete development of the individual and of the 

 number of individuals ; as there exists a zoological geography and a 

 botanical geography, which distinguishes and enumerates for each spe- 

 cies the most favored or most favorable regions there exists also a 

 mineralogical geography, which fixes the cantonment of particular 

 minerals in certain countries. In the Island of Elba, more than any- 

 where else, is found oligist iron ; in the Hartz and the Ural, ores, and 

 native metals ; in India, Brazil, and South Africa, gems and diamonds ; 

 in California and Australia, gold ; in Canada and Chili, copper ; in 

 Siberia, malachite ; and in Iceland, Iceland-spar. This study has been 

 elaborated for some substances tin, for example in the admirable 

 labors of Elie de Beaumont. 



Thus, since we have for minerals an embryology, an anatomy, a 

 nosology, a teratology, and a geography, a vast assemblage of facts 

 many of which are known and more unknown, we may also conclude 

 upon the existence of a mineral biology. When every one of the 

 chapters which it embodies shall have been treated experimentally, we 

 may come into a condition to formulate its laws. The artificial bar- 

 riers raised by our ignorance between the different branches of knowl- 

 edge will one after another be leveled. Natural history w T ill become 

 easy, like physics and chemistry, now that physics and chemistry, as 

 Lagrange foresaw, have become easy ; or, rather, all the sciences will 

 be consolidated into one science, which will be one because matter, 

 the object of its investigations, is one. Every time the mind of the 

 investigator escapes beyond the work of detail which he daily per- 

 forms in his laboratory, the contemplation of an ideal far removed, 

 but which he is certain he or those who will follow him will attain, 

 gives him new strength to go back to that daily labor, marks an ad- 

 vance, infinitely little but certain, toward that ideal. A glance over 

 its history shows how mineralogy has grown. It seems as if it were 

 conscious of the end toward which it is tending, of connecting the sci- 

 ences called natural with the exact sciences. As M. Pilo has happily 

 remarked, mineralogy has traversed the period of magic with the 

 alchemists, the empiric period with the experimenters of the seven- 

 teenth century, the naturalist's period with Linnaeus, Buffon, and 

 Werner, the geometric period with Haiiy, Delafosse, and Bravais, the 

 chemical period with Berzelius, and the physical period with Fresnel, 



