LIST OF ILLUSTRATIONS 



The farm equipment plants, soils, animals, tools, build- 

 ings Frontispiece 



Figure Facing Page 



1. Specimen plants for study 6 



2. The first effort of a sprouting seed .... 7 



3. Germinating seeds with roots 7 



4. To show that plant roots take water from the soil . 10 



5. To show that plant roots take food from the soil . 10 



6. A radish root, from which the stored food has been 



used to help produce a crop of seeds . . .11 



7. A sweet-potato root producing new plants . .n 



8. Sweet-potato roots 14 



9. Soy-bean roots 15 



10. A plow stopped in the furrow, to show what it does 



to the roots of plants when used for after-cultiva- 

 tion 18 



n. A corn-plant ten days after planting the seed . . 19 



12. To show where growth in length of the root takes 

 place 22 



13. Radish seeds sprouted on dark cloth . . . .22 



14. To show how water gets into the roots of plants . 23 



15. To show osmose 23 



16. To show that roots need air 26 



17. Comparison of fresh and boiled water . . .26 



18. Comparison of moist sand and puddled clay . . 27 



19. Comparing soils 32 



20. Water-test of soils 33 



21. To show what becomes of the water taken from the 



soil by roots 40 



xvii 



