RELATION OF SOILS TO WATER 4 1 



rod is heating make a shallow notch in the glass 

 with the wet corner of a file in the direction you 

 wish to make the cut. When the rod is hot lay the 

 end of it lengthwise on the notch. Very soon a 

 little crack will be seen to start from the notch. 

 Lead this crack around the bottle with the hot rod 

 and the bottom of the bottle will drop off.) (Fig. 

 23.) Make a rack to hold them. Tie a piece of cheese 

 cloth or other thin cloth over the small ends of the 

 chimneys. Then fill them nearly full respectively, 

 of dry, sifted, coarse sand, clay, humus soil, and gar- 

 den soil. Place them in the rack ; place under them 

 a pan or dish. Pour water in the upper ends of the 

 tubes until it soaks through and drips from the 

 lower end (Fig. 22). Ordinary sunburner lamp 

 chimneys may be used for the experiment by tying 

 the cloth over the tops; then invert them, fill them 

 with soil and set in plates or pans. The sand will 

 take the water in and let it run through quickly; 

 the clay is very slow to take it in and let it run 

 through; the humus soil takes the water in quite 

 readily. Repeat the experiment with one of the 

 soils, packing the soil tightly in one tube and leav- 

 ing it loose in another. The water will be found 

 to penetrate the loose soil more rapidly than the 

 packed soil. We see then that the power of the 

 soil to take in rainfall depends on its texture or the 

 size and compactness of the particles. 



If the soil of our farm is largely clay, what hap- 

 pens to the rain that falls on it? The clay takes 

 the water in so slowly that most of it runs off and 



