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Down! down! in headlong overthrow,
Horseman and horse, the foremost go,

Wild floundering on the field!
The first are in destruction's gorge,
Their followers wildly o'er them urge;-

The knightly helm and shield,
The mail, the acton, and the spear,
Strong hand, high heart, are useless here!
Loud from the mass confused the cry
Of dying warriors swells on high,
And steeds that shriek in agony !
They came like mountain-torrent red,
That thunders o'er its rocky bed;
They broke like that same torrent's wave,
When swallow'd by a darksome cave.
Billows on billows burst and boil,
Mantaining still the stern turmoil,
And to their wild and tortured groan
Each adds new terrors of his own;
XXV.

Too strong in courage and in might
Was England yet, to yield the fight.
Her noblest all are here;

Names that to fear were never known,
Bold Norfolk's Earl De Brotherton,

And Oxford's famed De Vere.
There Gloster plied the bloody sword,
And Berkley, Grey, and Hereford,
Bottetourt and Sanzavere,
Ross, Montague, and Mauley, came,
And Courtenay s pride, and Percy's fame-
Names known too well in Scotland's war,
At Falkirk, Methven, and Dunbar,
Blazed broader yet in after years,
At Cressy red and fell Poitiers.
Pembroke with these, and Argentine,
Brought up the rearward battle-line.
With caution o'er the ground they tread,
Slippery with blood and piled with dead,
Till hand to hand in battle set,
The bills with spears and axes met,
And, closing dark on every side,
Raged the full contest far and wide.
Then was the strength of Douglas tried,
Then proved was Randolph's generous pride,
And well did Stewart's actions grace
The sire of Scotland's royal race!

Firmly they kept their ground;
As firmly England onward press'd,
And down went many a noble crest,
And rent was many a valiant breast,
And Slaughter revell'd round,
XXVI.
Unflinching foot 'gainst foot was set,
Unceasing blow by blow was met;

The groans of those who fell
Were drown'd amid the shriller clang,
That from the blades and harness rang,
And in the battle-yell.
Yet fast they fell, unheard, forgot,
Both Southern fierce and hardy Scot;--
And O! amid that waste of life,
What various motives fired the strife!
The aspiring Noble bled for fame,
The Patriot for his country's claim;
This Knight his youthful strength to prove,
And that to win his lady's love;
Some fought from ruffian thirst of blood,
From habit some, or hardihood.
But ruffian stern and soldier good

The noble and the slave,

From various cause the same wild road,
On the same bloody morning, trode,
To that dark inn the Grave!

XXVII.

The tug of strife to flag begins,
Though neither loses yet nor wins,
High rides the sun, thick rolls the dust,
And feebler speeds the blow and thrust.
Douglas leans on his war-sword now,
And Randolph wipes his bloody brow,
Nor less had toil'd each Southern knight,
From morn till mid-day in the fight.
Strong Egremont for air must gasp,
Beauchamp undoes his visor-clasp,
And Montague must quit his spear,
And sinks thy falchion bold De Vere!
The blows of Berkley fall less fast,
And Gallant Pembroke's bugle blast
Hath lost its lively tone;

Sinks, Argentine, thy battle-word,
And Percy's shout was fainter heard,
'My merry-men, fight on!'-
XXVIII.

Bruce with the pilot's wary eye,
The slack'ning of the storm could spy.
'One effort more, and Scotland's free!
Lord of the isles iny trust in thee

Is firm as Ailsa-rock:
Rush on with Highland sword and targe,
I, with my Carrick spearmen, charge;
Now, forward to the shock!'

At once the spears were forward thrown,
Against the sun the broad-swords shone;
The pibroch lent its maddening tone,
And loud King Robert's voice was known→
'Carrick press on-they fail, they fail!
Press on, brave sons of Innisgail,

The foe is fainting fast!

Each strike for parent, child and wife,
For Scotland, liberty, and life,-

The battle cannot last!'

Edith, stationed on the hill with the camp-followers, hears the cry of the rallying host, and the notes of their trumnpets, " 'twixt triumph and lament;" and fearful of the event, passionately calls upon them to join their countrymen in the field. "That rallying force, combined anew, Appear'd, in her distracted view,

To hem the isles-men round;

O God! the combat they renew,
And is no rescue found!

And that look thus tamely on,

ye

And see your native land o'erthrown,
O! are your hearts of flesh or stone?'-
XXX.

The multitude that watch'd afar,
Rejected from the ranks of war,
Had not unmoved beheld the fight,
When strove the Bruce for Scotland's right;
Each heart had caught the patriot spark,
Old man and stripling, priest and clerk,
Bondsman and serf; even female hand
Stretch'd to the hatchet or the brand;
But, when mute Amadine they heard,
Give to their zeal his signal-word,

A frenzy fired the throng.-
Portents and miracles impeach
Our sloth-the dumb our duties teach-
And he that gives the mute his speech,
Can bid the weak be strong.
To us, as to our lords, are given
A native earth, a promised heaven;
To us, as to our lords, belongs

The vengeance for our nation's wrongs;

The choice, 'twixt death or freedom, warms
Our breasts as theirs-To arms, to arms!'
To arms they flew,-axe, club, or spear,-
And mimic ensigns high they rear,
And, like a banner'd host afar,
Bear down on England's wearied war."

To each canto are prefixed introductory verses. Of these the best are those opening the first, fourth, and fifth cantos. Those of the second are passable; of the third we may say the same-while those of the sixth are decidedly very inferior. We quote those of the fourth canto-a lofty tribute of admiration to the stupendous and solitary scenery of Scotland. "Stranger! if e'er thine ardent step hath traced The northern realms of ancient Caledon, Where the proud Queen of Wilderness hath placed,

By lake and cataract, her lonely throne; Sublime but sad delight thy soul hath known, Gazing on pathless glen and mountain high, Listing where from the cliffs the torrents thrown Mingle their echoes with the eagle's cry, And with the sounding lake, and with the moaning sky.

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ART. 6. NEW INVENTION.

Propulsion of Navigable Bodies, and Improvement in the Construction of Mills.

vigable bodies, introduced by an exposition of the causes of the great losses of power attending the operation of common

HAVING, in a previous number of water-wheels, I embrace the present op this work (for June), published some strictures on the propulsion of na

portunity to offer the following diagram, in further elucidation of my position.

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zontal propulsion, and perpendicular

exertion.

f. When the paddle has arrived at this position, its whole force is propulsive. This square represents the whole force of the paddle, divided horizontally and perpendicularly in the proportions of hand i, squares together equal to g; and so on till the paddle emerges.

therefore, no motion takes place in any direction.

If external force be applied to the vessel by sails, water-wheels, towing, &c. in any one direction, it has the immediate effect of relieving the water pressing in the same direction, from the resistance of the water pressing in an op posite direction, and that pressure, thus released, becomes active, and the vessel moves; hence it is that the shape of a ship's after-part is considered all-important by nautical men, in order that the pressure of the water may be received in the most advantageous manner. Now it has already been shown that external force cannot be applied by the operation of water-wheels, as heretofore, without an immense sacrifice of power. But it must be obvious that if power can be employed to remove the pressure of the water in any one direction, an equal pressure in a contrary direction will be released, and becoming active, will move the vessel with the same advantage as external power applied in the most favourable manner. Fortunately for mankind, nature has ordained that power can very easily be so applied, without any other waste than that of the friction of mechanism employed in the operation. How did the lucid intellect of WATT improve the mechanical effect of steam? not by adding to its power, but by removing a pre-existing natural resistance, ob

To this I may add, that the injurious tendency of the present system of propulsion, is, in effect, still further increased beyond the proportion already explained. Suppose a vessel of a certain capacity, having an engine capable of giving it a motion of eight miles per hour, if none of its power were wasted. But as threefourths of the power are wasted, an engine of four times the power, and more than four times the weight, must immediately be substituted-four times the quantity, and weight, of fuel will also be required. The boat must now be enlarged and strengthened to carry the additional burthen, and to sustain the prodigious action of a four-fold engine. Again the engine and fuel must be increased to propel the enlarged boat; and the boat further enlarged and made stronger still, to carry the doubly enlarged engine: proceeding thus, it is true, the engine's power gains at each remove on the boat's size, but does not overtake it until both are inordinately magnified. The engine being then, probably, of not less than six times the power of that originally provided—structing its natural action. and the boat enlarged one half. Yet, notwithstanding these extravagant incumbrances, steam-boats must be profitable, or they would not be continued. But since these mechanical imperfections are inseparable from the present system, they prove indisputably the existence of some egregious error in the application of the power of the primum mobile.

If we pause for a moment to inquire into the laws of statics, by which floating bodies are sustained quiescently in water, we shall find:

1st. The water exerts a perpendicular pressure upward beneath the whole area of the vessel, having a constant tendency to raise it a tendency as constantly resisted by the gravity (or weight) of the vessel, and therefore it does not rise.

2d. The water exerts a lateral pressure in every direction, against the sides of the vessel towards the centre, and has a tendency to move it in every direction-but as a body can only move, or be moved, in one direction, at one time, the opposite pressures, or tendencies to action, of the water, counteract and destroy each other;

The following simple experiment, within the compass of every one, exemplifies the principle of the discovery elucidated in my last communication, in a pleasing and conclusive manner :-Provide a small model of a boat with a projecting tube inserted at the head, beneath the water line, with a valve at its inward extremity -keep the valve closed by a thread applied to a small lever, so adjusted as to open the valve when the thread is severed-put the boat in water-divide the thread with a lighted taper, to avoid the possibility of accidental impulse from contact-the valve now opens, and the boat moves forward spontaneously its whole length, with accelerated velocity, thrusting the tube before it through the water. Why, if my principle be false, does not the water flow backward through the tube, and the boat remain stationary?—The boat is at length filled, and the water received by the tube being met by the internal opposite end of the boat, motion is impeded, and ceases of course-but were it convenient (it is not in this model) to bail the admitted water, the boats

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FIG. 1.

A. A. Surface of the water contained in a circular cistern or pan.

B. B. A model of a boat floating in the water at the circumference of the cistern.

C. The raceway attached to the boat. D. A siphon, one extremity terminating in the raceway; the other hanging over the cistern, the lower extremities of both legs being placed exactly on a level.

FIG. 2.

A. Bird's-eye view of the circular cistern, full of water. B. The boat, raceway, and siphon, connected to a pivot in the centre of the cistern, by an arm, merely to preserve the regular curvilinear direction when in motion.

C. A circular channel on the outside of the cistern, into which the outer leg of the siphon depends, and discharges water when the apparatus is in action.

Let us now imagine the siphon exhausted of air in the common manner, it of course becomes full of water.-This

water discharges itself at the outer leg, and the boat instantly advances with rapidity, in the direction of the arrow, and continues in motion, ad infinitum, if the emitted water be returned at intervals to the cistern. Now both legs of the siphon being of equal lengths and inclinations, it is manifest that the pressure of the water contained within it, cannot be the cause of motion, because that pressure operates equally in two opposing directions. The fact really is that the siphon by merely allowing the water opposed to the forward end of the raceway to flow off by its own gravity, the pressure of the external water behind the raceway becomes unballanced, and therefore active, and imparts motion to the boat, &c. &c. Thus the siphon, in this experiment, effectively performs the office of the water-wheel, as explained in my late disquisition, but cannot do more.

This, my newly-discovered use of the siphon, admits of very various application. Boats may be navigated on canals through its agency, without mechanical or animal power, simply by means of hydrostatic pressure, provided a gutter be

made to carry off the water discharged. If a proper figure be given to the siphon, and an increased length, and inclined spouts, added to the outer leg, the raceway may be omitted. Mills may be constructed with singular economy and advantage on this plan, particularly when the level of the adjacent country does not afford a great head of water ;-the siphon will then communicate motion to machinery from the centre of rotation, or at the circumference, as may be required. And, finally, the movement being nearly devoid of friction, may be variously employed to actuate petty machinery, on very advantageous principles. These latter applications of the siphon, operate on the principle of Barker's Mill, but entirely without the great loss of power proceeding from the vis-inertia of the

water, as explained by Dr. Olinthus Gregory, in his mechanical treatise.

But to return to the subject of the raceway, as applied to mechanical navigation, I find the principle may be brought into action, beneficially, by placing it at the head of a vessel, with two long cylindrical water-wheels, one on each side (as shown in the diagram) having their shafts parallel with the line of the boat's motion. The float-boards when in the water being placed obliquely with a gentle spiral backward inclination. When thus circumstanced, the raceway is baled laterally, and by a comparative slow mechanical action, the wheels revolving with about one-third of the boat's velocity;-a fact attended with great practical advantage.

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A. The boat advancing in the direction of the arrow.

B. The forward end of the raceway, C. D. The water-wheels, with inclined float boards, baling the raceway on each side.

These longitudinal water-wheels, may also be applied in raceways at the sides or sterns of vessels with equal advantage. It is a fact somewhat remarkable, that the idea of this negative application of power seems never to have suggested itself either to the ancients or moderns. The Phoenicians--the Egyptians--the Tyrians-the Greeks-the Carthaginians -and the Romans, had their single gallies, their biremes, triremes, &c. all moving by operation against the inertia of the water. The Italian gondolas are still navigated on a similar principle. The schemes of the French engineers are, without exception, modifications of the same idea. The British experimentalists have one and all followed the individual system. The Americans, in the persons of Fitch, Rumsay, Stevens, Allison, and Livingston, have pursued the same plan under various devices: and, lastly, Fulton, following the beaten track, produced results superior to all, just inasmuch as he applied a more powerful primum mobile.

Abandoning the law of statics, by which fluids rise spontaneously to their original level, the ancients erected those mighty structures called aqueducts;-the enlightened moderns effect their purposes by the more convenient ascent of water through tubes. In mechanical navigation the ancient system is still pursued ; but, why should not the natural law, acting with perfection in the first instance, be appealed to with corresponding efficacy in the second?

The grand object of propulsion being now achieved on equal terms, it is scarcely possible to contemplate the advantages resulting in a national point of view, (and I might even go further) without risking the charge of immoderate vanity from those who have not devoted their attention to the subject; but supported as I am, by the fundamental laws of nature, tested by repeated experiments, will I venture to call public attention to a matter fraught with consequences of high importance.

Let every one seriously reflect, that, if steam-vessels, supported as they now are, at an enormous cost, are deemed (and deservedly so) one of the proudest boasts of America, and one of her most distinguished blessings, where, in the long and brilliant perspective of succeeding ages, shall we seek a termination of the benefit to result from a discovery mul

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