APPENDIX. 



THE following simple directions are given for the benefit 

 of those who have no experience in science-teaching : 



The exhibition of specimens of soils, plants, fertilizers, 

 etc., and the performance of even a few experiments, will 

 av/aken in the minds of pupils a lively interest in the sub- 

 ject, cultivate the power of observation, and render the 

 work of teaching pleasant and practical. Many illustra- 

 tions, in addition to those mentioned, will doubtless suggest 

 themselves to the minds of teachers. 



The figures refer to corresponding numbers in the 

 text : 



(i .) Show to the class a specimen of soil, place a little 

 on the end of a table-knife or spatula, and heat it over an 

 alcohol-lamp until the organic matter is burned off. 



(2.) Exhibit to the class a sample of alluvial soil from a 

 creek or river bottom. 



(3.) Exhibit pieces of sulphur, carbon, phosphorus, iron, 

 lead, silver, etc., to illustrate what is meant by an element. 



(4.) Pulverize in a mortar a small quantity of potassium 

 chlorate, and mix with it about one-fourth its weight of 

 manganese dioxide (black oxide of manganese). Place the 

 mixture in a test-tube or small glass flask, and apply the 

 heat of an alcohol-lamp. Oxygen will be disengaged, as 

 may be shown by lowering into the flask or test-tube a 

 lighted splinter. The flame will be greatly increased, and. 



