204 INTRODUCTION TO GENERAL SCIENCE 



Materials : Sufficient sand, gravel loam, peat, clay, broken 

 stone, and samples of local soils, to fill the chimneys. 



a. Cover the small end of each chimney with cheesecloth, 

 and fill with different materials; place tumblers under each 

 chimney, and pour the same amount of water into each. 

 Time the flow of water through each. 



146. IMPORTANCE OF MOISTURE 



'We are now concerned with the importance of moisture to 

 the farmer. Water, and its uses, are treated under other 

 heads. Plants can only absorb their food when it is dis- 

 solved in water, and the amount of water is huge when com- 

 pared with the quantity of food which is taken up at the 

 same time. Then also, if the soil is not moist, it becomes 

 hard, and the plants cannot force their roots through it, in 

 order to obtain their food. In addition to this, a very large 

 percentage of all plants is actually water. Thus there may 

 be very rich soils which could support enormous growths of 

 vegetation, if it were not for the fact that the rainfall is very 

 slight. Many of our deserts, where they have been watered 

 artificially, have become the best producing places on earth. 



References : 



1. 1304 : 337-338. Importance of Moisture. 



2. 1407 : 28. Absorption of Water by Roots. 



3. 1503 : 143-146. Water Supply for Plants. 



4. 1601 : 155-156. Amount of Water Used by Crops. 



5. 1605 : 84-85. Importance of Soil Water. 



6. 1702 : 155-157. Water Content of Plants. 

 a. 1602 : 21-23. Plants and Water. 



6. 1604 : 124-127. The Necessity for Moisture. 



c. 1606 : 47-48. Why Moisture is Important. 



d. 1608 : 43-46. Kinds and Uses of Soil Moisture. 



