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three decimal [)laces ; lower his record if lie forgets the fractions of a 

 minute in tlie angle between all primary and secondary planes, the angle 

 of refraction, of polarization, etc., etc. Now, if you succeed in obtaining 

 that from any student, you have unearthed a prodigy ; your victim has 

 accomplished a feat equal, if not superior, in point of lively interest, to 

 the learning of the old Greek roots, which, some say, could only have 

 been extracted from the devil's garden; or the operation of conning an 

 answer to a few hundred jiroblems, without ever knowing how one of 

 them was obtained. Vou have developed his bump of memory, but at the 

 imminent I'isk of permanent injury to his bump of common sen^. 

 Finally, Determinative Mineralogy, if not studied in connection with 

 the two other branches, offers no beiter advantage; for, though after going 

 through a series of mechanical experiments, and then laying your hand on 

 a mineral, you turn over a few pages of Mr. Urush and say : This is the 

 name of my specimen, you do not know the reason of your state- 

 inent. You are ignoi-ant of this mineral's place among the various 

 classes of mineral substances, and you approach it pretty much in the 

 same light as a blindfolded ambassador led by the hand through the for- 

 tifications of a besieged city. Such a process may be useful to the 

 practical mineralogist who has studied no Chemistry, and who cannot be 

 said even to have studie.l Mineralogy, but you do not find in it that which 

 should ever be the guiding star of the teacher of youth — the formation 

 of the mind. 



Chemistry is absent from the theoretical part. The principle of 

 crystallization is expounded in such a manner as to leave the student 

 under the impression that only natural minerals crystallize. As 

 for the laws regulating chemical composition, they are not men- 

 tioned ; nor can it be alleged that the student is supposed to have 

 studied them before, as no allusion is ever made to that anterior 

 knowledge. On the contrary, the mechanical manipulation necessary 

 for the most simple experiments with acids is given in detail, but not a 

 word written to point out the chemical ijeaction which takes place. In 

 the Descriptive the same exclusiveness is maintained in all but the 

 grou^^ing of the mineral species. The iron ores, copper minerals, silica, 

 are put together, but not one of the numerous tests indicated by Chem- 

 istry to detect the presence of iron, copper, or that ubiquitous silica is 



