5. From this it will be seen how necessary water is to the life of a plant. Ordinary soil consists of small particles of mineral substances, such as chalk, iron and flint, as well as of bits of vegetable matter dead leaves, rotten wood, and so on. There must be water to dissolve this plant food before the roots can take it in.

6. When the roots of a great tree spread out very wide, as they must do in their search for such large quantities of food, so also do the branches of the tree extend; and thus the rain which drops from the ends of these great spreading branches falls right on to the place where the hungry rootlets are waiting below to feed the tree.

7. Stagnant water in the soil is really harmful to the plants. Farmers therefore drain off surplus water, by putting in drain pipes, or by digging furrows and ditches across their fields.

8. It might be thought that the roots of plants take out of the earth so much of its nourishing substances, that the soil must become poorer and poorer, till at last the plants die simply because there is nothing left for them to feed upon. To provide against this, the air, the rain, and the sun are constantly acting on the earth, in such a way as to cause changes which really keep adding to these nourishing substances.

9. Still, if a farmer wishes to grow a large

supply of food in a short space of time, he puts manure on his land, which enriches the soil, and so enables him to raise better crops. In order to keep a plant healthy its roots must absorb oxygen, a gas which is always plentiful in the open air. It is for this reason that gardeners dig and rake their beds; for by so doing the air is let in between the particles of soil, and thus reaches the roots.

1. There are some substances in the soil which will not dissolve in water, but will dissolve in acid. Now the sap of plants is generally acid, and some of it passing down through the roots into the soil changes the mineral food into such a form that it can be sucked up through the roots.

2. Every bit of the food which a plant obtains from the earth has to pass through tiny roots called root-hairs. These, which are the real feeders, are very thin delicate threads. Therefore the food

must be split up into the very smallest particles, before it can pass through these tiny root-hairs into the root.

3. There are many kinds of roots. Some plants have walking roots, as the strawberry, or as we might call it the "strayberry," and the house

RUNNER OF STRAWBERRY.

leek; and some have creeping roots, as the twitch or couch grass, whose underground stems are the farmer's pest, and which he often fails to get rid of

even when he plows them up.

4. The habit of extending by underground stems has been acquired by the plant to protect it from destruction; for rabbits and other gnawing animals like to nibble the lower parts of plants and trees, but they never follow the stem after it enters into the soil.

5. The rootlets of the daisy and all grass plants grow in a cluster, like a number of strong threads or fibers. A carrot has a long, thick, tapering root, and its life history is very different. different. Its seeds grow into plants, but no flowers appear upon them during the first year. At the approach of the cold season the stem dies down; but the root,

protected by the soil, lives on through the winter. In spring it sends up new stems, which, in season, bear flowers and fruit.

6. The taproot, as it is called, having now done its work, dies. A plant that lives only for one year has no need to store up food in a taproot, and therefore has fibrous roots like the grass. When we cultivate the carrot or the turnip for food

DIAGRAM OF A
TAPROOT.

ROOT OF THE
CARROT.

ROOT OF THE
RADISH.

we take care to pull it during the first year while it is plump and has all its goodness still within it.

7. If a sound, dry onion be placed in a damp cellar, we may note how soon it changes its form and condition there. It begins to sprout; it feels soft, and looks shrunken. Leaves grow out at the top, but they are of a much paler green than those which would grow outside in a garden where

there is plenty of light; at the same time a large number of long, stringy rootlets grow out from the bottom of the onion.

8. What has made the onion sprout? It is simply that the bulb has obtained from the damp air of the cellar sufficient moisture to start it growing. It is no longer a sound, dry onion; it now feels smaller, softer, and is much shrunken, because the new leaves and roots that have sprouted out have all been fed upon the stored-up food which was contained within the bulb.

9. Flowering plants are divided into three great classes- annuals, biennials and perennials. Annuals are those which live only one year; as they require no storehouse of food they all have fibrous roots. Biennials are those which do not flower until the second year, and in most cases die after their seed has ripened; these, like the carrot and the turnip, have large taproots. Perennials are those which live and flower year after year for a number of years.

10. Many roots are used by man. Some are used for food, such as the radish and the parsnip; some for medicine, such as arrowroot and Turkey rhubarb (which latter is grown in China). Ginger is a root; beet root furnishes sugar; and many indeed are the uses to which the roots of plants are put.