SUGGESTIONS TO TEACHERS. 



TRUE teaching requires activity and original work on the part of 

 the teacher. To rely mainly upon the text-book, and simply 

 require pupils to commit to memory the statements of the text, is not 

 teaching. 



The aim should be to stimulate in the minds of pupils the habit 

 of observing and thinking for themselves. The text should simply 

 serve as a guide, or starting point, for the work of the class. 



This is particularly true of subjects related to the natural sciences, 

 like those of which the present work is composed. Many topics in 

 the text are necessarily treated with brevity, but it is expected that 

 teachers will avail themselves of the opportunity to amplify and illus- 

 trate them with familiar examples. 



The questions at the end of each chapter may be used for review 

 exercises or for examinations. They may also be used in daily reci- 

 tations, but teachers will naturally ask many similar questions of 

 their own. 



The teaching will be rendered much more interesting and effectual 

 by the free use of object lessons and simple experiments. Those 

 who are accustomed to teach the natural sciences and are supplied 

 with apparatus for the purpose, need no suggestions upon this point. 



The outfit of a chemical laboratory is not necessary, however, as 

 the ingenious teacher will find abundant means for the purpose 

 within reach. Specimens of rocks, soils, and plants from the neigh- 

 boring fields, pots of soil with a few varieties of seeds and of fer- 

 tilizers, for experiments in the growth of plants, a small quantity 

 of some common and familiar chemicals purchased for a few cents of 

 the nearest apothecary, and a small microscope, either purchased or 

 borrowed for occasional use, are among the means available. 



It will serve a useful purpose, particularly with the older pupils, 

 to have at hand, for reference and comparison, other works on chem- 

 istry, geology, physical geography, botany, and agriculture. 



The subject is naturally interesting, and, if wisely presented, can 

 not fail to afford enjoyment to both teacher and pupils, and to yield 

 satisfactory results, 

 (vi) 



