MICHIGAN ACADEMY OF SCIENCE. 145 



A STUDY OF SOILS BY YOUNG STUDENTS. 



J. A. JEFPERY. 



In preparing an outline for the study of soils in rural schools, it is 

 borne in mind that the pupil, the condition and the teacher will each 

 have a bearing upon how closely any outline shall be followed. 



The following short outline is one which I would suggest, subject, as 

 indicated above, to modification. The time required for the work will 

 depend on the time at the teacher's disjiosal. In the ordinary country 

 school the work would have to be done largely during the spring and fall 

 terms. 



Apparatus Required. 



Little can be done without some apparatus. 



It would be desirable, of course, to have a laboratory with a lot of good apparatus, but 

 even with simple and crude tools, one is often enalDled to obtain excellent results. 



A torsion balance weighing to 1-10 gram, glass tubes, glass funnels, glass jars, filter 

 paper, graduates and evaporating dishes are desirable. 

 ■ This article is written for a laboratory supplied with apparatus as follows: 



One kitchen scale with dial. -weighing from one ounce to 24 pounds, price 90 cents. 

 One dozen gallon jars — of the deep sort. 

 One dozen common glass tumblers. 



One and one half dozen riuart tin fruit cans (tomato cans) with open end melted off by placing can, 

 open end down, on a hot kitclien stove for a few minutes. 

 One dozen tops of baking powder cans. 



One common eight ounce graduate such as can be bought in most grocery stores. 

 A few do.7en screw cap bottles, .seven-eights inch by five and one-half inches, or thereabouts. 

 One small bottle of ammonia. 

 One small alcohol lamp. 



A Soil Collection. 



(a) Have each member of the class bring a quart sample of soil. This sample should 

 be obtained by digging a hole with perpendicular walls to the depth of the plowed soil, 

 or, in virgin soil, to the depth of the soil proper as indicated by the darker color due to the 

 presence of the larger quantities of organic matter. In muck soils take samjjle to depth 

 of six inches. Mix thoroughly Isefore taking the quart sample. 



(b) These soils should be air dried, thoroughly mixed, and smaller samples taken from 

 these to preserve. A screw cap homeo, 7 inch bv 5| inches, makes a very convenient 

 receptacle in which to preserve samples. 



(c) Have the pupils place these samples in groups so far as they may be able to on the 

 basis of appearance, feel, etc. If they have any difficulty in this let the teacher suggest 

 and later, if necessary, complete the classification. 



There are likely to be in this lot of soils, sandy soils, loams, clays, and muck soils with 

 intervening modifications. In some cases sub classifications on the basis of color, might 

 be required. Or some special form of soil, such as an alluvial, might be brought in. 



(d) If these vials of soil could now be mounted in some permanent form, for reference 

 from time to time, say upon heavv cardboard with light copper wire, it would be helpful. 



(e) Have samples of the sub-soils brought in the same manner for a depth of six inches 

 below the depth of the first sample. Dry, bottle, and place each with its soil. 



(f) It would be well to carefully save the remaining soils after bottling the samples. 



Composition of Soils. 



(a) Have each pupil study a sample of the soil he has brought, (and later, samples of 

 soil brought by the others) and let him as far as possible determine what materials com- 

 pose it. 



(b) In a qualitative way the relative amounts of organic matter, fine material, and sand 

 of each soil may be determined: — 



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