'Reflections on some Mineralogical Systems. 381 



those who profess another mineralogical belief than that of 

 M. Haiiy. It is ranked in the same species as simple car- 

 bonated lime, although it often contains but one-third car- 

 bonate of lime, and The remainder iron or manganese : evi- 

 dent marks also indicate an additional structure of the cleav- 

 age in the direction of the great diagonal, which leads to 

 solids of two or more forms. 



We have observed that there exist vacuums between the. 

 molecules of bodies, in which foreign matter may lodge. 

 It may therefore happen that particles of iron or oxicied 

 manganese are deposited in the vacuums of carbonated 

 lime : when this is the case, we have the mineral in ques- 

 tion. But it does not thence follow that the integral mo- 

 lecule should change its form, as the oxided iron does not 

 enter it, and as it, in fact, undergoes no change in its che- 

 mical composition. One of the indispensable properties of 

 the molecule of minerals being not to vary but by two 

 indications at once, then whatever enters not the integral 

 molecule, although it forms a part of the mineral, should 

 not change it : this law is constant, whether it relates to the 

 quantity of extraneous substances, or to their nature, their 

 form, or their tendency to crystallization. But as foreign 

 matter can interpose itself between the molecules with 

 which it is surrounded or enveloped, it may influence their 

 relative dispositions; whence will result secondary forms, 

 which shall differ according as the spaces between the mo- 

 lecules are empty, or more or less tilled. The passage of 

 light may also be obstructed by the interposition of opaque 

 matter, and the colour must participate in that of the 

 interposing substances. The molecules being enveloped 

 may be further removed from immediate contact, and thus 

 offer a greater facility of separation : the junctures also may 



This supposed improvement, tberefoie, of HauVs arrangement, by subdi- 

 viding and transposing ihe varieties of tiiis subspecies, exists more in 

 names than characters; Tor even those of specific gravity and pf astracting 

 the magnet depend solely on the preponderance of iron over rhe manganese ; 

 and sometimes the i;iuntity of manganese is ve*-y considerably greater than 

 that of the inn, without any difference in exterior character. To change, 

 torture, or reject a system for such a tnping and merely apparent anomaly, 

 would betray m<jr«J ignorance of the diversity of rfafure than scientific ex- 

 piariencej t«> attempt to modulate an otherwise complete system to - 

 things, would be to pay more attention to exceptions than to rules, and 

 evince nothing but tpe foppery o!' minuteness, which never can exist in 

 minds expanded by true science. Mr. Chenevix's chemical explanation, 

 indeed, of this phenomenon is pei fectly sufficient, and more satisfactory 

 than M. B scheme of minute division, which may be sometimes 



very right aud sometimes very wrong. His epithet brunissonte, or brown- 

 ing, adopted from the Germans, is equally as applicable to his sparry iron 

 as to this carbonated lime ; that of Haiiy, although long, is correct and in- 

 teiligible, — ferro-manganesiferous carbonated lime. — Trans. 



be 



