MINERALS AND ROOKS. 171 



the materials should be collected by the pupils. Something 

 to start upon may be found in every section, and fortunately, 

 it is not difficult to obtain from outside sources specimens 

 enough of a few kinds to go round the class. 



Where to get Minerals. — Minerals are to be had by searching 

 in the fields, river banks, gravel pits, quarries, stoneyards 

 and marble cutters' yards. Certain dealers keep them for 

 sale. Bituminous coal, anthracite, rock salt, gypsum, asbestos, 

 sulphur, graphite, soapstone, and mica are generally procurable. 

 Variety may be increased by exchanging specimens that you 

 can spare. A small collection of minerals, properly boxed, is 

 ornamental as well as useful. See the engraving of such a 

 box in " Correlation of Nature Study and Manual Training," 

 opposite page 46. 



Mineral Study and Physiography. — The study of that part 

 of physical geography called physiography, the part that is 

 concerned with the dynamic and chemical effects of water, 

 atmosphere, and change of temperature upon the solid 

 substances that form the earth's surface — is interesting, useful 

 and educative. It cannot be prosecuted very successfully 

 without some study of the nature and properties of these 

 substances; and just as the sciences of botany and zoology 

 should be founded upon the nature study of plants and 

 animals so should physics and inorganic chemistry and geology 

 grow out of the similar study of the forces and materials of 

 the inanimate world within the circle of the learner's observa- 

 tion. Physical and chemical experiments made to discover or 

 establish truths related to objects the pupils are studying are 

 more educative, at least to beginners, than if performed apart 

 from their applications like so many imaginary problems in 

 mathematics. (Page 10.) 



Elementary Lessons on Minerals. — In " Public School 

 Nature Study," pp. 157-165, there are given introductory 



