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Thou, only thou, art little here,

Like worth unfriended or unknown, Yet to my British heart more dear Than all the torrid zone.

Thrice welcome, little English flower!
Of early scenes beloved by me,
While happy in my father's bower,

Thou shalt the blithe memorial be:
The fairy-sports of infancy,

Youth's golden age, and manhood's prime, Home, country, kindred, friends,—with thee Are mine in this fair clime.

Thrice welcome, little English flower!
I'll rear thee with a trembling hand;
O for the April sun and shower,

The sweet May-dews of that fair land,
Where DAISIES, thick as starlight stand
In every
walk!—that here might shoot
Thy scions,* and thy buds expand,
An hundred from one root!

Thrice welcome, little English flower!
To me the pledge of hope unseen;
When sorrow would my soul o'erpower
For joys that were, or might have been,
I'll call to mind, how, fresh and green,
I saw thee waking from the dust,
Then turn to heav'n with brow serene,
And place in God my trust.

* Scions.] Offshoots.

MONTGOMERY.

LESSON 86.

MACHINERY.

A MACHINE is a contrivance to enable us to employ force in the most effective way. Sometimes we want to increase our force and at others to obtain greater speed. Sometimes it is desirable to produce one kind of motion by means of another kind—as when, by turning round a wheel, we sucker of a pump up and down.

move the

These, and many more results, are produced by machinery. By combinations of the different mechanical powers, machines have been constructed, capable of executing the most complicated works of every kind.

A machine may be moved by hand. A pump is a simple instance of such a machine. It is much less labour to raise water from a well in this way than if we were to draw it up in a pail.

But when machines began to be used, it was soon found that other forces besides that of our hands could be employed. A waggon is, as I before said, a machine for drawing weights along a road, and the strength of a horse is used in this machine. Horses are constantly employed in different machines: sometimes by turning round a wheel they move the sucker of a pump, and so draw up water from below the earth; sometimes corn is threshed by a machine, which is turned by wheels moved round by horses in the same manner.

In Scripture we read of two women grinding at a mill. This was done by means of two mill-stones,

the lower one being fixed, and the upper one moved round upon it, by means of handles. This was a hand-machine for grinding corn.

In the course of time, some person thought of finding out other means for moving the upper millstone. The first plan was to make use of the wind. Four great arms with sails were fixed on to an axletree in such a manner, that when the wind blew against them they turned the axle-tree round. When this had been done, all that was necessary was to fix a toothed wheel to the axle-tree, which worked upon another toothed wheel, and thus several toothed wheels were set in motion, the last of which turned round the upper mill-stone. This is called a windmill. There are contrivances in the mill for winnowing the flour, and doing other things, by means of different wheels, all moved by the great axle-tree.

Wind is a very powerful force, but it is irregular. Sometimes there may not be wind enough to move the sails, and at other times it may be so violent that a mill cannot be worked with safety. Except in great storms, it is easy to guard against the sails being moved too quickly, but there is no way of making up for the absence of wind.

Water is not liable to these objections. A stream does not usually fail except in very dry seasons, and the water may be kept from running away by means of dams or embankments. Water exerts a force which does not appear so violent as that of the wind, but is steady and really very great. So when the idea of a mill was once started, men soon began to use water instead of wind whenever there was a convenient stream. They dam up the water to a height

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above the level of the stream, and place a large wheel at the opening through which the water falls into the stream below. This is the principal wheel of the mill, and is turned round by the force of the falling water. The great axle-tree of this wheel answers to the great axle-tree of the windmill, by means of which all the smaller wheels are set in motion.

But a stream of water is not to be found in every place, and a far more powerful force has been discovered than either water or wind: this is steam. Steam is the vapour produced by boiling water. We know when the water boils in a kettle, by the steam issuing from the spout. If the steam were not permitted to escape through the spout, it would soon force open the lid. Steam will burst open strong iron vessels, if enclosed in them, and has been applied to construct a gun, in which a quantity of steam having been shut up, at last expands with such violence, as to send out a volley of bullets with as much force as a large cannon. This force of steam which can so easily be produced, and may be so destructive, has, by the ingenuity of man been brought under complete management, so that we may say of steam, what is commonly said of fire, "It is a bad master but a most excellent servant.”

Without describing the steam-engine, it will be sufficient to say that the force of steam is employed to move an iron rod up and down, and by this means, with the help of a crank, to turn a wheel, as has been before described. The axle of this wheel answers to the great axle of the windmill, or watermill, and sets in motion a system of wheels and rollers arranged to suit the purpose of the particular machine.

The force of steam is much greater, more regular, and more easily produced than that of either water or wind, and is capable of performing what neither wind nor water could effect. But since the requisite machinery is expensive, and requires very careful managment, both wind and water are still very

commonly used in the more simple machines.

LESSON 87.

THE USE OF MACHINERY.-PART I.

THE PAPER-MAKING MACHINE.

IT has been said in a former lesson that every tool may be properly called a machine, and man uses tools in almost every work he undertakes. More contrivance is necessary to produce linen out of the fibres of a plant than to dig the ground, or saw up wood into planks; but the spade and the common weavers' loom are both machines-both are moved by hand, and they differ only in the one being more simple than the other, and it is usual to call a spade a tool, and a loom a machine.

But we can scarcely speak of the use of machinery without including the application of other forces than the hand. It is indeed the ability to apply such forces that makes machinery so valuable.

In order to understand the application of machinery, we must first consider the nature of the work as it is performed by hand. The paper-making machine will afford us a beautiful illustration.

The mode of paper-making by hand has been described in another place. When the rags have

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