=Experiment.=--Plant some seeds in tumblers or in boxes filled with sand and in others filled with good garden soil. Keep them well watered and watch their progress for a few weeks (see Fig. 5). The plants in the garden soil will grow larger than those in the sand. The roots evidently must get food from the soil and those in the good garden soil get more than those in the poorer sand. Another important function of plant roots then is to take food from the soil for the plant. You know how thick and fleshy the roots of radishes, beets and turnips are. Well, go into the garden and see if you can find a spring radish or an early turnip that has sent up a flower stalk, blossomed and produced seeds. If you are successful, cut the root in two and notice that instead of being hard and fleshy like the young radish or turnip, it has become hollow, or soft and spongy (see Fig. 6). Evidently the hard, fleshy young root was packed with food, which it afterwards gave up to produce flower stalk and seeds. A fourth use of the root, then, is to store food for the future use of the plant. =Experiment.=--Plant a sweet potato or place it with the lower end in a tumbler of water and set it in a warm room. Observe it from day to day as it puts out new shoots bearing leaves and roots (see Fig. 7). Break these off and plant them in soil and you have a number of new plants. If you can get the material, repeat this experiment with roots of horse-radish, raspberry, blackberry or dahlia. From this we see that it is the work of some roots to produce new plants. This function of roots is made use of in propagating or obtaining new plants of the sweet potato, horse-radish, blackberry, raspberry, dahlia and other plants. [Illustration: FIG. 4. To show that plant-roots take water from the soil, the plants in _A_ are suffering from thirst. _B_ has sufficient water.] [Illustration: FIG. 5. To show that plant roots take food from the soil. Both boxes were planted at the same time.] [Illustration: FIG. 6. A radish root, from which the stored food has been used to help produce a crop of seeds. Notice the spindle shaded seed-vessels.] [Illustration: FIG. 7. A sweet-potato root producing new plants.] We have now learned five important things that roots do for plants, namely: Roots hold plants firmly in place. They absorb water from the soil for the plants. They absorb food from the soil for the plants. Some roots store food for the future use of the plant. Some roots produce new plants. How do the roots do this work? To answer this question it will be necessary to study the habit of growth of the roots of our plants. HABIT OF GROWTH OF ROOTS