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قراءة كتاب A Book of Natural History Young Folks' Library Volume XIV.
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id="pgepubid00027">ANIMALS, BIRDS, AND FISHES
BY
DAVID STARR JORDAN, LL.D.
This volume is made up from the writings of naturalists who have told us of the behavior of animals as they have seen it at first hand and of the beginnings and the growth of life so far as they know about it. In selecting these from the wealth of available material the editor has been guided by this rule: The subject matter must be interesting to young people; it must be told in a clear and attractive style; and most important of all, it must deal with actualities. We have seen in the last few years a marked revival of nature studies. This has led to a wider range of interest in natural phenomena and in the growth and ways of animals and plants. If this movement is not to be merely a passing fad, the element of truthfulness must be constantly insisted upon. If a clever imagination, or worse, sentimental symbolism, be substituted for the truth of nature, the value of such studies is altogether lost.
The essence of character-building lies in action. The chief value of nature study in character-building is that, like life itself, it deals with realities. One must in life make his own observations, frame his own inductions, and apply them in action as he goes along. The habit of finding out the best thing to do next and then doing it is the basis of character. Nature-study, if it be genuine, is essentially doing. To deal with truth is necessary, if we are to know truth when we see it in action. The rocks and shells, the frogs and lilies, always tell the absolute truth. Every leaf on the tree is an original document in botany. When a thousand are used or used up, the archives of Nature are just as full as ever. By the study of realities wisdom is built up. In the relations of objects he can touch and move, the child finds the limitations of his powers, the laws that govern phenomena, which his own actions must obey. So long as he deals with realities, these laws stand in their proper relation. “So simple, so natural, so true,” says Agassiz. “This is the charm of dealing with nature herself. She brings us back to absolute truth so often as we wander.”
So long as a child is led from one reality to another, never lost in words or abstractions,—so long this natural relation remains. “What can I do with it?” is the beginning of wisdom. “What is it to me?” is the beginning of personal virtue.
By adding near things to near, the child grows in Knowledge. Knowledge, tested and set in order, is Science. Nature-study is the beginning of science. It is the science of the child. The “world as it is” is the province of science. In proportion as our actions conform to the conditions of the world as it is, do we find the world beautiful, glorious, divine. The truth of the world as it is must be the final inspiration of art, poetry, and religion. The world, as men have agreed to say that it is, is quite another matter. The less our children hear of this, the less they may have to unlearn. Nature studies have long been valued as “a means of grace,” because they arouse the enthusiasm, the love of work, which belongs to open-eyed youth. The child blasé with moral precepts and irregular conjugations turns with fresh delight to the unrolling of ferns or the song of birds.
Nature must be questioned in earnest, or she will not reply. But to every serious question she will return a serious answer. “Simple, natural, and true,” she tends to create simplicity and truth. Truth and virtue are but opposite sides of the same shield. As leaves pass over into flowers, and flowers into fruit, so are wisdom, virtue, and happiness inseparably related.
This little volume is a contribution to the subject matter of Nature Study. It is the work of students of nature, and their work is “simple, natural, and true,” in so far as it is represented here.
Leland Stanford Jr. University,
California, April 22, 1902.
A BOOK OF NATURAL HISTORY
THE WONDER OF LIFE
(From His Science Primer, Introduction.)
By PROFESSOR, T. H. HUXLEY.
Every one has seen a cornfield. If you pluck up one of the innumerable wheat plants which are fixed in the soil of the field, about harvest time, you will find that it consists of a stem which ends in a root at one end and an ear at the other, and that blades or leaves are attached to the sides of the stem. The ear contains a multitude of oval grains which are the seeds of the wheat plant. You know that when these seeds are cleared from the husk or bran in which they are enveloped, they are ground into fine powder in mills, and that this powder is the flour of which bread is made. If a handful of flour mixed with a little cold water is tied up in a coarse cloth bag, and the bag is then put into a large vessel of water and well kneaded with the hands, it will become pasty, while the water will become white. If this water is poured away into another vessel, and the kneading process continued with some fresh water, the same thing will happen. But if the operation is repeated the paste will become more and more sticky, while the water will be rendered less and less white, and at last will remain colorless. The sticky substance which is thus obtained by itself is called gluten; in commerce it is the substance known as maccaroni.
If the water in which the flour has thus been washed is allowed to stand for a few hours, a white sediment will be found at the bottom of the vessel, while the fluid above will be clear and may be poured off. This white sediment consists of minute grains of starch, each of which, examined with the microscope, will be found to have a concentrically laminated structure. If the fluid from which the starch was deposited is now boiled it will become turbid, just as white of egg diluted with water does when it is boiled, and eventually a whitish lumpy substance will collect at the bottom of the vessel. This substance is called vegetable albumin.
Besides the albumin, the gluten, and the starch, other substances about which this rough method of analysis gives us no information, are contained in the wheat grain. For example, there is woody matter or cellulose, and a certain quantity of sugar and fat. It would be possible to obtain a substance similar to albumin, starch, saccharine, and fatty matters, and cellulose, by treating the stem, leaves, and root in a similar fashion, but the cellulose would be in far larger proportion. Straw, in fact, which consists of the dry stem and leaves of the wheat plant, is almost wholly made up of cellulose. Besides this, however, it contains a certain proportion of mineral bodies, among them, pure flint or silica; and,