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crack or hollow of the stem, and soon shows itself in the form of a round knob, which, when cut through, exhibits the infant flower enveloped in numerous sheaths; these open and wither away as the flower enlarges, until at the time of its fulness, but very few remain. The blossoms rot away not long after their expansion, and the seeds (spora) are raised with the pulpy mass.

This giant flower may well be esteemed the wonder of the vegetable world; and although several others, similar to it in form and habits, have been found, none have as yet been discovered that equal it in size. A small species has been mentioned by Dr. Horsfield; but his flower, instead of measuring three feet across, only measured three inches. A second very magnificent species, measuring two feet across, has been discovered in a small island near Java, called Nusa Kambangan, which has been described and figured by Blume, in his Flora Java, and from this work our second and third figures have been taken. By the natives it is called Patma, and hence the botanical name proposed is Rafflesia Patma, (see Fig. 2.) Another of these vegetable paradoxes,

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figured also by Blume, is a native of the province of Buitenzorg, in the western parts of Java, and grows at the

height of from 1200 to 1500 feet above the level of the It has been called Brugmansia Zippelii, (Vide

sea.

Fig. 3.)

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So

All these curious plants agree in several circumstances. In the first place, they have no proper roots of their own, and derive their nourishment from the vegetables on which they grow. In the second place, they have no stems, the flowers being seated on the vines that support them. Thirdly, they are destitute of leaves, the flowers being enclosed only by scales, which are purplish, or brownish, and resemble the outer coverings of buds, or rather the chaffy scales of other clinging plants; for, deriving their nourishment through the leaves of another vegetable, they do not require leaves of their own. that here we have plants consisting of flower only, neither root, stem, nor leaves being present. And what is still more curious is, that, although the largest and most magnificent flowers in the world, they have very little in common with other flowering plants. They have no proper seeds, but are multiplied by spores, similar to the spawn of mushrooms, to which, indeed, their general form bears very great resemblance. The flower-leaves are of a mushroom-like substance, and smell like tainted beef; they contain no hollow vessels, like most other

flowering plants, but consist of cells alone, like the mushroom-tribe, and they arise from beneath the bark of the cissus, which becomes enlarged by their growth, and very much resembles that false covering which some of that tribe have which grow upon living plants; raising the outer surface into tumors, and bursting it as they become more fully grown, such as the blights and blasts of corn, and so forth. Hence these stupendous flowers, which are six to nine feet in circumference, show their likeness to the most lowly of the mushroom tribes, some of which are so minute as scarcely to be visible to the naked eye.

ILLUSTRATIONS OF NATURAL PHENOMENA.

THE TIDES.

EVERY body knows how useful the Tides are. Upon the sea-coast we constantly see a number of ships, all waiting at anchor for some hours, while the crews are able to take their rest. We keep looking at them, and, at a certain time, without any change of wind having taken place, we see them all busy setting their sails and weighing anchor, and, in a few hours more, they are all out of sight they were, in fact, waiting for the change of the tide. If the wind was unfavorable, they could never make head against it, as long as the tide was against them too; but with the tide in their favor, they can pursue their voyage, even against an unfavorable wind.

In rivers, the use of the tides is seen still more plainly. The tide brings not only a current, but a whole supply of water every twelve hours; and the continual change, which can be quite calculated upon, is just as useful as having a wind constantly fair up and down a river, alternately, for a certain number of hours every day.

Besides the immense importance of the tides to navigation, no one can calculate how conducive they are to health and cleanliness. Such a river as the Thames is thoroughly washed out, twice a day, by a current, car rying with it, towards the sea, all the drainage of a population of a million and a half of people, and as often bring

ing up clear water and fresh air. It is a system of lungs, breathing regularly twice in about twenty-four hours.

Hundreds of people are deriving benefits from this beautiful arrangement of Providence, without thinking at all about it; and many others are contented to see such changes happen, without trying to comprehend how they are brought about. Now it is certain, that the more we study the works of Nature, the clearer proof we find of the wisdom of God who contrived them all; and the tides are a very remarkable instance of a vast variety of beneficial effects arising from one simple cause.

We shall endeavor to show how the tides are produced: and we hope none of our readers will be prevented from trying to understand the explanation, under the notion that it is too difficult to be comprehended without previous study: we promise them that the subject requires only ordinary attention, and plain common sense, and that it will well repay the trouble of attending to it.

It is soon seen that the tides are in some way occasioned by the moon; for the time of high and low water comes back to the same hour whenever the moon is at the same age.

The height of the tide on different days plainly depends also upon the age of the moon. The highest tides are always found about the time of new and full moon, and the lowest when the moon is in her quarters.

What is to be explained then is, why the waters should rise and fall twice in rather more than twenty-four hours, and how this fluctuation is connected with the position of the moon. For this purpose, we will first see what the effect of the moon would be, if the whole earth were covered with water, and we shall afterwards easily discover what changes will be made, when we consider the actual condition of the globe made up of land and water.

TIDES OF AN OPEN OCEAN..

It is well known that the moon is a solid body, which goes round the earth every month, in a direction from West to East, and, from the real motion of the earth on its axis, appears to move round from East to West every

day. Supposing, then, м to be the moon, and c the centre of the earth, there is some point, A, upon the surface of the earth, which is nearest to the moon, and another point, B, exactly opposite, which is furthest from the moon. Now

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every solid body, such as the moon, is found tọ draw towards it any other body, by a force which is called gravitation, and is really the same force by which a stone falls to the ground; and this force is the greater, the nearer the attracted body is to that which attracts; thus A would be attracted by м more than c is, and c would be more attracted by м than в is. If these three particles, A, C, and B, were quite at liberty to move towards м at the end of any time, as a minute, A would have moved towards м through a greater space than c had, and c through a greater space than B had; hence A would be further from c, and c further from B, than each was at first. And if the motion of в be regarded only with reference to the point c, considered as at rest, the effect would be the same as if it were really drawn away from c, by the attraction of some other body (m) exactly opposite to M.*

If, then, A C B were a sphere of water, a particle at A or at B would be lifted a little above its ordinary level,

*It may appear somewhat strange to those who have not thought before about the matter, that an attraction towards м should cause a rise of the waters in the part opposite to m; and it may be worth while to explain the principle upon which it depends a little more clearly. Suppose then A c B to be three equal small balls of iron, floating on pieces of cork, and one foot asunder; then suppose a powerful magnet to be applied at M, which draws A through three inches, c through two inches, and в through one inch; if the bodies

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be then stopped, as at a c b, it is plain that the distance of a from c is now one foot two inches, and the distance of b from cis one foot one inch, instead of one foot. The effect, therefore, of the attraction of Mhas been to separate the two bodies, в and o, as well as A and o.

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