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express, in the following lines, the sentiments which so naturally spring from the contemplation of such a subject as the "Nests of Birds:"

"It wins my admiration

To view the structure of that little work-
A bird's nest. Mark it well within, without.
No tool had he that wrought; no knife to cut;
No nail to fix; no bodkin to insert;

No glue to join; his little beak was all:
And yet how nicely finished! What nice hand,
With every implement and means of art,
And twenty years' apprenticeship to boot,
Could make me such another?"

EXERCISES.

1. The Migration of Birds. 2. The Migration of Fishes. 3. The Provision of Insects for their Young. 4. The Hive of the Bee. 5. The Habitation of the Beaver. 6. Instinct displayed by the Lower Animals in Self-preservation.

3. Write a short illustration of the following Transformations.

MODEL.-The Frog.

Nothing, perhaps, in the whole course of nature, is more calculated to excite wonder and reflection than the changes through which some animals pass before they attain their perfect state. Of this kind of development we shall take the frog as an example.

The spawn of the frog is deposited in stagnant pools early in spring. It consists of a transparent gelatinous mass, throughout which the eggs, appearing like little black dots, are distributed at regular intervals. In process of time, which varies according to the temperature of the water in which they are placed, the little animals burst from their prison, and become what are called Tadpoles. In this state they live on vegetable matter. They are furnished with a long tail, which materially assists them in moving through the water; and they breathe, like fishes, by means of gills. The gills of the tadpole, however, are not concealed by any

covering, but appear like fins on each side of the head. As the transformation proceeds, these gradually disappear, two small feet begin to bud forth, as it were, near the tail, and in a few days the hind legs are completed. The form of the mouth changes, and the animal loses all appetite for vegetable food. The fore legs or arms are next produced, and, when these are completed, the tail drops off. The frog now appears in its perfect state, and breathes by means of lungs.

"Thus," says Goldsmith, "the frog, in less than a day having changed its figure, is seen to change its appetite. So extraordinary is this transformation, that the food it fed upon so greedily before is now utterly rejected: it would even starve if supplied with no other. As soon as the animal acquires its perfect state, it becomes carnivorous, and lives entirely upon worms and insects. But as the water cannot supply these, it is obliged to quit its native element, and seek for food upon land, where it lives by hunting worms and taking insects by surprise."

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4. Write a short illustration of the Utility of the following subjects.

MODEL.-The River.

The river may, in a general sense, be said to perform the same office in the economy of nature as the artery does in the human body. Pregnant with properties essential to the support of vegetable existence, it springs from its source, and in its progress repairs the waste, and sustains the vigour, of the gigantic frame of which it is itself a part. Returning to the ocean, the great reservoir from which it was at first derived, it is again sent forth to repeat, in endless succession, its indispensable functions.

Besides supplying the vital necessity of water, rivers are, in many respects, an inestimable blessing to the countries through which they flow. Wherever they appear, the land is like a garden; where they are absent, it is a desert. Refer, for example, to the map of Egypt, and behold the Nile, its fruitful banks studded with innumerable towns, pursue its majestic and fertilising course. Beyond the sphere of its beneficial influence, the country on the east and on the west, exposed to the action of a burning sun, and unrefreshed by the moisture of a single stream, presents the aspect of an arid and uninhabitable wilderness. The advantages of rivers, in respect of their influence upon the soil, and in imparting coolness to the surrounding atmosphere, is thus most apparent in tropical countries. Under the combined operation of heat and moisture, vegetation in these regions reaches the maximum of luxuriance. "The Ganges," says Macaulay, "rushing through a hundred channels to the sea, has formed a vast plain of rich mould, which, even under the tropical sky, rivals the verdure of our English April. The rice fields yield an increase such as is elsewhere unknown. Spices and sugars, vegetable oils, are produced with marvellous exuberance."

Rivers, by facilitating intercourse between the different countries of the world, and thus materially contributing to the progress of commerce, have been highly conducive to civilisation and to the wealth and prosperity of nations. Most of the great commercial cities of the world, it will be found, are mainly indebted for their importance to a favourable situation on the bank of some navigable river, such as the Thames, the Elbe, or the Neva. Viewed as a means of transit, in a more limited sense, the value of rivers is not to be estimated. The immense quantities of timber, for example, that are annually floated down the Rhine, the Mississippi, and other streams, would, without such means of conveyance, be totally unavailable for the various purposes to which that useful material is so ex

tensively applied. The Rhine rafts, which are constructed upon an immense scale, deserve a passing notice. The wood that is floated down its tributaries, being collected at a considerable distance from its mouths, is formed into an immense raft, sometimes 800 or 900 feet in length, and 60 or 70 in breadth. A number of huts is erected on it for the accommodation of the workmen and rowers, amounting to several hundreds, so that the enormous mass has the appearance of a floating village.

The natural advantages of rivers as a medium of communication have been multiplied by human industry in the cutting of canals. There are upwards of one hundred canals in England; and they cover the surface of Holland like network.

The moral and physical aspect of Africa, which is comparatively destitute of rivers, affords a striking instance of their beneficial influence. In the absence of these vivifying agents, a great part of its surface is condemned to perpetual sterility; while, for the same reason, the interior being in a great measure excluded from communication with civilised nations, its inhabitants are consequently in a state of ignorance and barbarity.

It is one of the remarkable instances of God's goodness to man, that the enjoyments to be derived from His innumerable gifts do not depend on their usefulness alone. Thus, in contemplating the life and beauty that a noble river imparts to the landscape, we are filled with a sentiment of pleasure entirely irrespective of its mere utility; and the sense of its importance to our physical wants is lost in the more exquisite gratifications that pertain to the feelings. As the river is not in this respect a solitary example of the Divine benevolence, we trust that the consideration of such a subject may always be accompanied by those emotions of reverence and gratitude which it is so well fitted to excite.

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1. Write a short explanation of the following Properties of Matter.

MODEL.

Impenetrability.

Matter is distinguished by certain properties which are termed essential or general. The essential properties that is to say, those without which we cannot conceive matter to exist―are Impenetrability, Extension, and Figure.

Impenetrability is that property by which every body occupies a certain space, so that when two bodies are pressed together, they are not lost in each other, however great the force employed. In the case of two solids, this principle is so apparent as to require no demonstration; while its effect in every other instance, though not so easily perceptible, is equally certain. Thus, before a vessel can be filled with water, the air that is contained in the vessel must be displaced, as we may prove by a very simple experiment. Let a glass vessel be forced under water with its mouth downwards, and it will be found that the water will not rise to the top until the air that is contained in the vessel is allowed to escape. It is upon this principle that the use of the diving-bell depends. Again, if we drop a stone into a vessel filled with water, as much of the water will run over as is equal to the bulk of

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