Outlines of Lessons in Botany Part 1

Outlines of Lessons in Botany.

by Jane H. Newell.

Part I.

From Seed to Leaf.

PREFACE.

In this study, as in all scientific teaching, the teacher's aim should be to foster in his pupils the power of careful observation and clear expression. The actual amount of knowledge gained at school must needs be small, and often quickly forgotten, but the habit of right study is an invaluable possession.

The former method of teaching Botany was confined almost wholly to dry, technical cla.s.sification. The pupil learned to find the name and order of a plant, but its structure, its habits, its life in short, were untouched by him. We know now that Nature is the best text-book. The pupil should first ask his questions of her and try to interpret her answers; then he may learn with profit what those who better understand her speech have to tell him.

This method of teaching, however, requires much, very much, of the teacher. He must be himself intelligent, well trained, and able to give time to the preparation of his lessons. It seems to us, who are but amateurs, as if it were impossible to teach thus without a thorough comprehension of the whole field. Our own ignorance oppresses us so much that we feel tempted to say that we cannot attempt it. But if the work of leading children to observe the wonders about them is to be done at all, it must be done by us, who are not masters of our subject, and we must find out for ourselves how we can best accomplish this result, since we have so little to guide us.

It is with the hope that the experience of one who has tried to do this with some fair amount of success may be of use to other puzzled experimenters, that I venture to write out some outlines of lessons in Botany for beginners.

The method of beginning with the simpler forms of life is one that appeals to the scientific tendencies of the day. It seems logical to begin with lower forms and work up to the higher. But this method is only suitable for mature minds. We do not teach a child English by showing him the sources of the language; he learns it by daily use. So also the beginning of the study of any Natural Science by the young should be the observation of the most obvious things about them, the things which they can see, and handle, and experiment upon naturally, without artificial aids. Therefore this book concerns itself only with the Flowering Plants.

The author believes that the simplest botanical study should afford the means of identifying plants, as a large part of the student's pleasure in the science will be the recognition of the things about him. The present volume affords the basis for future cla.s.sification, which Part II, on flowers, will develop. It is, doubtless, as good a way, perhaps the best, to begin with a single plant, and study root, stem, leaves, and flowers as belonging to a whole, but the problem is complicated by practical difficulties. In our climate there are but two months of the school year when flowers are easily obtained. On the other hand, the material for these lessons can be got throughout the winter, and the cla.s.s, well trained in methodical work, will begin the study of flowers at the season when every day brings some fresh wonder of beauty.

The author will receive gladly any criticisms or suggestions.

JANE H. NEWELL.

175 Brattle St., Cambridge

INTRODUCTION.

The lessons here outlined are suitable for children of twelve years of age, and upwards. For younger pupils they would require much adaptation, and even then they would not be so good as some simpler method, such as following the growth of one plant, and comparing it with others at every step. The little ones profit most by describing the very simple things that they see, without much reference to theories.

The outlines follow the plan of Dr. Gray's First Lessons and How Plants Grow, and are intended to be used in connection with either of those books. The necessary references will be found at the end of every section.

The book contains also references to a course of interesting reading in connection with the subjects of the lessons.

The lessons may begin, like the text-books, with the subject of Germination, if the seeds are planted before they are required for use, but it is generally preferable to use the first recitation with the cla.s.s for planting the seeds, in order to have them under the direct care of the pupils. Some general talks about plants are therefore put at the beginning to occupy the time until the seedlings are ready for study.

Some Nasturtiums (_Tropaeolum majus_) and Morning-Glories should be planted from the first in boxes of earth and allowed to grow over the window, as they are often used for ill.u.s.trations.

I.

PLANTS AND THEIR USES.[1]

[Footnote 1: This section may be omitted, and the lessons begun with Seedlings, if the teacher prefer.]

What is Botany? The pupils are very apt to say at first that it is learning about _flowers_. The teacher can draw their attention to the fact that flowers are only a part of the plant, and that Botany is also the study of the leaves, the stem, and the root. Botany is the science of _plants_. Ask them what the Geranium is. Tell them to name some other plants. The teacher should keep a few growing plants in the schoolroom for purposes of ill.u.s.tration.

Ask them what else there is in the world besides plants. By this question the three kingdoms, animal, vegetable, and mineral, are brought up. It will give occasion for a discussion of the earth and what it contains, the mountains, formed of rocks and soil, the plants growing on the earth, and the animals that inhabit it, including man. Let them name the three kingdoms with some example of each. Which of these kingdoms contain living things? The words _organic_ and _inorganic_ can be brought in here. An _organ_ ([Greek: Ergon], meaning work) is any part that does a special work, as the leaves, the stem of a plant, and the eye, the ear of animals.

An _organism_ is a living being made up of such organs. The inorganic world contains the mineral kingdom; the organic world includes the vegetable and animal kingdoms.

One's aim in these lessons should always be to tell the pupils as little as possible. Try to lead them to think out these things for themselves.

Ask them how plants differ from animals. They will say that plants are fixed to one place, while animals can move about; that plants have no will or consciousness, and that animals have. These answers are true when we compare the higher animals with plants, but the differences become lost as we descend in the scale and approach the border land where botanist and zoologist meet on a common ground. Sea-anemones are fixed to the rock on which they grow, while some of the lower plants are able to move from place to place, and it is hardly safe to affirm that a jelly-fish is more conscious of its actions than is a Sensitive Plant, the leaves of which close when the stem is touched.

There is no real division between animals and plants. We try to cla.s.sify the objects about us into groups, according to the closeness of their relations.h.i.+ps, but we must always remember that these hard lines are ours, not Nature's. We attempt, for purposes of our own convenience, to divide a whole, which is so bound together that it cannot be separated into parts that we can confidently place on different sides of a dividing line.

1. _Plants as Food-Producers_.--The chief distinguis.h.i.+ng characteristic of plants is one that the pupils may be led to think out for themselves by asking them what animals feed upon. To help them with this, ask them what they had for breakfast. Oatmeal is mentioned, perhaps. This is made from oats, which is a plant. Coffee and tea, bread made from wheat, potatoes, etc., all come from plants.[1] Beef, b.u.t.ter and milk come from the cow, but the cow lives upon gra.s.s. The plant, on the other hand, is nourished upon mineral or inorganic matter. It can make its own food from the soil and the air, while animals can only live upon that which is made for them by plants. These are thus the link between the mineral and animal kingdoms. Ask the scholars if they can think of anything to eat or drink that does not come from a plant. With a little help they will think of salt and water. These could not support life. So we see that animals receive all their food through the vegetable kingdom. One great use of plants is that they are _food-producers_.

[Footnote 1: Reader in Botany, for use in Schools. Selected and adapted from well-known authors. Ginn & Co., Boston, New York and Chicago, 1889.

I. Origin of Cultivated Plants.]

This lesson may be followed by a talk on food and the various plants used for food.[2]

[Footnote 2: The Flour Mills of Minneapolis: Century Magazine, May, 1886.

Maize: Popular Science News, Nov. and Dec., 1888.]

2. _Clothing_.--Plants are used for clothing. Of the four great clothing materials, cotton, linen, silk, and woollen, the first two are of vegetable, the last two of animal origin. Cotton is made from the hairs of the seed of the cotton plant.[1] Linen is made of the inner fibre of the bark of the flax plant. It has been cultivated from the earliest historical times.

[Footnote 1: Reader in Botany. II. The Cotton Plant.]

3. _Purification of the Air_.--The following questions and experiments are intended to show the pupils, first, that we live in an atmosphere, the presence of which is necessary to support life and combustion (1) and (2); secondly, that this atmosphere is deprived of its power to support life and combustion by the actions of combustion (2), and of respiration (3); thirdly, that this power is restored to the air by the action of plants (4).

We have the air about us everywhere. A so-called empty vessel is one where the contents are invisible. The following experiment is a good ill.u.s.tration of this.

(1) Wrap the throat of a gla.s.s funnel with moistened cloth or paper so that it will fit tightly into the neck of a bottle, and fill the funnel with water. If the s.p.a.ce between the funnel and the bottle is air-tight, the water will not flow into the bottle.

[Ill.u.s.tration: FIG. 1.]

Do not explain this in advance to the pupils. Ask them what prevents the water from flowing into the bottle. If they are puzzled, loosen the funnel, and show them that the water will now flow in. In the first case, as the air could not escape, the water could not flow in; in the second, the air was displaced by the heavier water.

Ask the pupils why the air in a crowded room becomes so difficult to breathe. Could a person live if he were shut up in an air-tight room for a long time? Fresh air is necessary to life. The teacher may explain that it is the oxygen in the air that supports life. Air is composed one-fifth of this gas and four-fifths of nitrogen. The gases are mixed and the nitrogen simply dilutes the oxygen, as it were.

Fresh air is necessary to support combustion as well as life. Ask them why we put out a fire by throwing a blanket or a rug over it. The following experiment ill.u.s.trates this.

(2) Take a small, wide-mouthed bottle, covered with a card or cork. To this cover fasten a piece of bent wire with a taper on the end. Light the taper and lower it into the jar. It will burn a few seconds and then go out. Raise and light it again, and it will be extinguished as soon as it is plunged into the bottle. This shows that the oxygen of the air is used up by burning substances, as it is by breathing animals.

[Ill.u.s.tration: FIG. 2.]

The following experiment shows that fire will not burn in an atmosphere of gas from our lungs.