37 



2. Cliemical Properlies, relating: to the chemical composition of the 

 soil, aixi the chemical changes which take place in the soil. 

 :;. Biological Properties, relalinj; to the life in the soil. 



(a) The microscopic plants, Bacteria, which oxidize the materials 

 of the soil. 



(/') Those org-anisms which break up or decompose the soil com- 

 pounds. 



(c") Those organisms which enrich the soil. 

 (1) Collect samples of the diflerent kinds of soils mentioned above, 

 and label the samples in bottes or vials. 

 (2.) Make a map of your farm. 



(3.) Locate the different soils on this farm on the map, giving a 

 delinite color to each variety of soil. 



(4.) To what extent has erosion agents, such as rains, running water, 

 etc., modified the surface of the farm since Glacial Times? 



(;3-) Collect or find samples of alluvial soils, residual soils. 



(6.) Determine the depth of the humus soil in the woods ; in land 

 which has borne but one crop. 



(T.) At what depth do you find the subsoil in the different fields. 



(8.) To what extent are the crops of the farm influenced by differ- 

 ences in the soil ? Are some fields better adapted for certain crops than 

 •other fields. 



(9.) Determine the physical properties of the various soils collected 

 as per question I. 



LXV. Experiments with Soils. 



1. The power of loose soils to retain moisture.. 



2. The power of compact soils to retain moisture. 

 :'. The rate of rise of gapillary water in soils. 



4. Relation of texture of soils to germination. 



5. Texture of different soils after rain. 



0. The conservation of moisture, value of mulches. 

 T. Mechanical analysis of soils. 



LXVI. School Gardens. 



For each student : one hoe, one garden rake, one garden line, four 

 corner pegs, two dozen 6-inch plant labels, and a note-book. 



1. Special Topics for discussion and investigation : 



((/) The site and aspect of the garden. 



(h) The soil and its improvement by spade-work, draining an|d ma- 

 nuring. 



