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1818.

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.

Or

Yes! 'twas sublime, but sad.-The loneliness Loaded thy heart, the desert tired thine

eye;

And strange and awful fears began to press
Thy bosom with a stern solemnity.
Then hast thou wish'd some woodman's cottage
nigh,

Something that show'd of life, though low
and mean,

Glad sight, its curling wreath of smoke to spy, Glad sound, its cock's blithe carol would have been,

children whooping wild beneath the willows green.

Such are the scenes where savage grandeur wakes

An awful thrill that softens into sighs; Such feelings rouse them by dim Rannoch's lakes,

In dark Glencoe such gloomy raptures rise: Or farther, where, beneath the northern skies, Chides wild Loch-Eribol his caverns hoar But, be the minstrel judge, they yield the prize Of desert dignity to that dread shore, That sees grim Coolin rise, and hears Corisken G.

roar.

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ART. 6. NEW INVENTION.

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

AVING, in a previous number of

vigable bodies, introduced by an exposition of the causes of the great losses of power attending the operation of common water-wheels, I embrace the present op

H work (for June), published portunity to offer the following diagram,

some strictures on the propulsion of na

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. g. This square represents the whole force of the paddle, divided horizontally and perpendicularly in the proportions of h and i, squares together equal to g; and so on till the paddle emerges.

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 and the boat enlarged one half. Yet, notwithstanding these extravagant incumbrances, steam-boats must be profilable, 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 cach other;

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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 opposite 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, obstructing its natural action.

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 fromn 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 boat's

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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 applica tion. 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;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

tiplying, in six-fold ratio, the present effect of power? rendering a few horses efficient as the most powerful steam engine; saving its cost, its current expenses, and its other inconveniences; added to those of the massy floating fabric indispensable to support the ponderous action of the mechanical mammoth? Under these circumstances, I say, what daring imagination shall prescribe limits to mechanical navigation?-The frail canoe, and the majestic ship, are alike susceptible of its advantages-and a period may ere long arrive, when mankind, rousing from the lethargic influence of antiquated habit, shall with one voice exclaim, the land is our resting place, but the water is our road! C. A. BUSBY,

No. 2. Law Buildings.

July 10th, 1818.

Postscript.-Having perused in the last number of this Magazine a description of Mr. Staples' "AIR BOAT," which has, I find, been supposed by some of that gentleman's friends to assimilate itself to my plan, I perceive the mode of propulsion there explained, is that of exhausting certain troughs attached to the boat, by means of what are termed " Plungers," ," working on the principle of a pump, assisted by appropriate valves-the whole being actuated by an Air Engine, as a primum mobile.

Referring to my Catalogue of Schemes, it appears that the exact idea originated with the great Franklin, being suggested by the learned doctor as a problematical improvement on the plan of M. Bernouilli. (Vide, Transactions of the Philosophical Society of Philadelphia, Dec. 2d, 1785.) The same method has also been tried frequently in England, and finally a patent was obtained by Mr. James Linaker, in London, July 14, 1808, for various modifications of the same principle. (Vide, Repertory of Arts, second series, vol. 16.) These plans have not been

pursued further, because the pressure of the atmosphere, upon which Mr. Staples places so much reliance, was found to act, unavoidably, in the worst possible direction, having an effectual tendency to force the water backward upon the valves, and thus impede the boat's progress.

The suggested improvements to the trough of Mr. Staples' inclined wheel, would seem to trench upon the principles developed in my Essay-but the application is so imperfect, that I am convinced Mr S. cannot have made the experiment. I shall, therefore, never interfere with its adoption. If, in addition to the closed valve described behind the inclined wheel, Mr. S. had added lateral openings in the trough, also behind the wheel, the effect would have been improved; for the water would then have found vent on each side, instead of being compelled to rise above the trough, (at a great loss of power) in order to obtain a passage.

66

An Air Engine," previously suggested by the aeronaut, Montgolfier, was patented in England, about four years since. (Vide, Repertory of Arts, 1815.)—Many expensive experiments (some of which I witnessed) were made under the superintendence of the first mathematicians and mechanicians-but finally the idea was abandoned. The ingenious Mr. Murray, Engineer, of Leeds, (England) has also been many years engaged in a similar pursuit.

The statement of these facts, since Mr. Staples would seem to be unacquainted with them, is not intended to detract from the ingenuity, or personal originality, of his ideas; particularly as I am informed the subject of which he has treated, is foreign to his ordinary vocations. I cannot, therefore, omit to express my regret that the zeal of his friends should have made it necessary for me to explain mat ters of record, perhaps not generally known. C. A. B.

ART. 7. ORIGINAL COMMUNICATIONS. To the Editors of the American Monthly Magazine.

GENTLEMEN,

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fleece of the Caramanian Goats to the

manufacture of hats.

3. Description of a most curious fossil fish, from Westmoreland, Oneida county, N. Y.

As I think them all interesting to science, art, and the country, I place them at your disposal, and assure you at the same time of my highest esteem and regard. SAM. L. MITCHILL. New-York, July 14, 1818.

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