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and the short notice for its insertion, makes it necessary that the description should be compressed in as small a compass as possible; and as the operations of the steam engine have become familiar, I purpose exhibiting this engine in an appropriate representation prefixed to this article, in which it will appear as connected with my improvements, instead of my circular engine, which will be more fully described in a work I purpose publishing, which will embrace the whole system and the advantages to be derived from its application to all kinds of mechanical purposes where motion and force are required, and especially to the propulsion of navigable bodies. We have seen that the application of steam is cheaper than that of common air rarified; that rarified condensed air is less expensive than steam; and that rarified fixed air is more economical than rarified condensed air. Hence I purpose employing that agent, especially in long passages. Fixed air may readily be obtained, and at a small expense. When the engine is to be actuated by fixed air, the vessel in which it is contained is to be connected with the "receiver;" and when the communication is open, the superior gravity of the fixed air causes it to enter the "receiver," and displace the atmospheric air contained therein. The communication between the receiver and the rarifiers being also open, the fixed air also takes the place of the common air in those vessels. During this operation, the communication between the rarifiers and the engine are shut. The attention of the engineer is now directed to the air pump, connected with the receiver and also with the engine, through the medium of the contractors, by suitable conducting pipes, for the purpose of exhausting the common air out of these vessels. When this operation is performed, the communication between one of the rarifiers and the engine is opened: the heated air then rushes out on the piston, which is propelled by its expansion; this operation gives motion to the main condensing or air pump; hence the expanded air is drawn out of the cylinder of the engine into the contractor, which is so situated at the side of the boat as to be completely immersed in a quantity of cold water, that is constantly thrown on it, and discharged at the side of the boat. Now it is an axiom that heat decreases as it recedes from the source from which it sprung; being absorbed by the surrounding bodies, until they are brought to an equilibrium. Hence, as the heated air is extended in
the contractors in as thin a sheet as possible, and as the motion of the water is rapid and continual over the whole exterior surface of the contractor; it follows that absorption must be rapidly carried on; by which means the heat is drawn out of the included air, and it shrinks into a small compass as effectually as by mechanical pressure: in this contracted state, it is forced into the "receiver" by the condensing pump, in the mean time, the heated air in the other rarifier is expanding on the piston, causing it to descend: it is then draws out of the cylinder of the engine, by the operation of the condensing pump, and passes through its "contractor," when the same operation is repeated as in the first instance; and the contracted air returned to the "receiver," in a state of density similar to the air included therein. From the "receiver" it is injected into the "rarifier," E. by a small powerful pump, operating upon the hydrostatic principle, and so on.
Thus by the alternate expansion and contraction of the same quantity of fixed air, which is not expended, a continued motion is produced. The motion of the engine is communicated to the plungers that operate on the water, by means of an escapement (H) which I have contrived for that purpose. The upper part of the piston-rod of the engine, consists of two strong parallel bars, connected together, as at H. H. having teeth in their sides which front each other. The shafts (to which the piston-rods &c. are attached, by means of cranks projecting fron it) is placed between, having firmly attached to its centre part a short cross bar (11.) or pallet, calculated to be operated upon by the teeth of the rack. The teeth are so disposed, that after a tooth on one side of the frame has raised one end of the pallet and is leaving it, a corresponding tooth on the other side is coming in contact with the depressed or opposite end of the pallet, and raises it in a similar manner, and so on in succession,-the same operation being repeated in the reverse motion of the frame. The uppermost tooth on one side, and the lowest on the other, are both a little longer than the others, and form the escapement; and are for that purpose, moveable in sockets regulated by springs, to permit the last tooth to react on the pallet it had just left. It is evident, without any further descrip tion, that this cross bar or pallet must be moved alternately up and down by each succeeding tooth, both in the upward and downward motion of the piston rod of the
engine, without intermission, and that
consequence of this new
A considerable quantity of cold water being required to absorb the heat contained in the rarified air in the contractors, I was led to think of some method of obtaining it from under the boat, and with as little expense of power as possible. On reviewing the operations of the plungers in motion, I perceived that a part of the reaction of the water on the stern was lost, being spent in pursuing the plungers in their returning motion;to prevent this, I placed a valve in the entrance of the inclined part of each of the trunks, and furnished the plungers with valves so constructed as to operate on the principle of a lifting and forcing pump ;the consequence was that I obtained a supply of water from the forward part of the boat, and the water under the stern, instead of pursuing the plungers as heretofore, was prevented by the valves in the trunks on which the water now reacted. By this method of operating, I soon discovered, that I had not only brought into _mosphere and the lateral pressure of the the boat a considerable quantity of water water against the stern and sides of the for the use of the contractors, without vessel:while it was excluded from the loss of power, but had relieved the forward bows by the removal of the water from part of the boat from a part of the resis- that part into the vessel, by the operation tance it sustained from the pressure of the of the pumps. Hence a new and impor incumbent water. Hence the application tant application of power, which will be of a valve in each trunk is all-important, in proportion to the power expended by the and distinguishes this application from all engine in raising the water. The quantiothers of a similar nature that have not ty of water raised will be in proportion to the surfaces of the pistons, and the respecsucceeded merely from a want thereof. tive heights to which it may be raised, the velocity of the boat will be in proportion to the motion of the pistons, which may be increased at pleasure. It then became a matter of calculation to ascertain whether the pressure thus obtained was equivalent to the force of the engine as applied in the first instance-and I was satisfied that this new mode of application, combined in less compass, all the advantages of the former in a more perfect degree. After carefully reviewing this operation, it occurred to me that the arrangement was susceptible of further improvement-there would be convenience in reversing the motion of the boat, and also in suspending the effects of the
A little reflection induced me to see how far I could improve this effect by making a more perfect vacuum under the boat. With this intention I removed all the trunks and plungers, except two, leaving one at each side of the vesselthe plungers in these two were then placed in a perpendicular position, and had united to their trunks a similar trunk placed on each side-the valves were now taken from the plungers and they were fitted to work air-tight-a valve was placed in the bottom of each trunk of the plungers-one of the lateral trunks left entirely open, the other furnished with two valves at the extremity connected with the submerse-trunk. The
operating power. To effect these objects, a pair of upright sliding valves, with lifting rods attached to them, were placed in each submersed trunk, near the centre, on each side of the perpendicular trunks. When both of these valves are raised or pushed down, the motion of ths boat is suspended. When the boat is in motion in any direction, one valve is up while the other is down-and when it is required to reverse the motion of the boat, the operation of the valve is also reversed. This arrangement suggested the idea of furnishing the trough of the inclined wheel with valves for the purpose of producing the effect of the vacuum thus obtained, though in an imperfect degree. With this intention a perpendicular valve with a lifting-rod attached to it, was placed in the trunk, on each side of the wheel, for the purpose of altering or suspending the motion of the boat, &c. The effects produced by these valves were new and surprising. When the water-wheel is put in motion, it removes the water out of the trunk, or trough part of it, which is under the wheel; while this operation is going on, the pressure of the atmosphere and the gravity of the water are partially removed from the forward to the after part of the trunk operating on the valve behind the wheel, which is down while the other is up. Hence the boat advances forward, and the trunk is supplied with water, which is resisted partially by the entering paddles, and, in proportion, assists the wheel in its progress, while the water thrown out contributes to increase the effects of the pressure of the atmosphere and the gravity of the water. Hence according to the velocity of the wheel so will be the quantity of the water displaced, and the vessel will advance in proportion. The application of this principle is new and interesting, and, though greatly inferior to the other indirect applications, will be attended with many advantages.
It remains to give a description of the peculiar form and construction of the boat alluded to in the preceding remarks, which I have denominated an Air Boat, accompanied with necessary explanations.
Description of the Air Boat.
A vessel ought to be constructed so as to answer the particular purpose for which she is intended. When she is intended to sail by means of mechanical force, her form should be different, because when sails are used, she is then acted upon by two elements, the wind and water, and requires a greater degree of stability to
be able to carry a press of sail,-considerable depth in the hold for the cargo, long keel, and little breadth to prevent her falling to leeward. When she is to sail by mechanical force, her form and size should be very different. For this purpose the bottom should be formed quite flat, (to sail as much as possible on the water,) and the sides made to rise perpendicular from it, without any curvature; which would not only render her more steady, as being more opposed to the water in rolling, but likewise more convenient, accommodating, &c. while the simplicity of her form would contribute greatly to the ease and expedition and economy with which she might be fabricated. Diminishing the draft of water is undoubtedly the most effectual method of augmenting the velocity of the vessel, but as it proportionably diminishes her hold of the water, and renders her more liable to be driven to leeward, this defect is remedied by the trunks under her bottom, which are an excellent substitute for a keel. By means of these side trunks she will be kept steady in the greatest gale, quite easy in a great sea, will not strain in the least, and never take in water on her deck; and when at anchor, will ride more upright and even than any other vessel can do. Her extreme breadth should be no more than the 5th or 6th part of her length: her bows a little curved to break the force of the water, and her stern something narrower than the bows, having a gentle in clination from the stem to the stern, to promote the action of the atmosphere and the water on the sides.
I think in the preceding remarks that I have established the following facts:
1st. That the power of atmospherical air and fixed air, increased by condensation and heat, as digested and arranged by me, is not only a very great, but the most eligible and most powerful agent for mechanical purposes.
2d. That in applying this power, a circular engine, on my construction, is the most useful of any other: and that by the simple escapement of the piston-rod of the steam engine, I have given it an advantage in reciprocating movements it had not before.
3d. That in the present steam-boat system there is an aggregate loss of nearly three-fourths of the power of the engine: and that on my plan the whole force of the engine can be applied without diminution, and with the one-fiftieth part of the fuel usually consumed in the present method. Hence my method of applying the
Proposals have been issued for publishing in the City of Washington, a new periodical paper, (three times a week) to be
JOHN I. STAPLES. Flushing, 25th June, 1818.
I. I. The cranks attached to the piston ends of the air pump, condenser, receiver, and plungers, &c.
K. M. The furnace with two small forcing pistons to keep up the fire, and also to discharge the smoke into water near the side of the vessel.
L. The forcing pistons in the chimnies or smoke funnels.
ART. 10. LITERARY AND SCIENTIFIC INTELLIGENCE.
N. N. The upright sliding valves in the submersed trunks to regulate the motion of the boat.
N. B. The piston, rods, &c. are elevated above the deck for the purpose of explanation. The "contractors" are not shown.
entitled, The Tribunal of the People, and
DODGE & SAYRE., ofreative York, National Inquisitor; edited by a Society
propose to publish on the Atonement. By Edward D. Griffin, D. D. of Newark, N. J.
A seventh newspaper is commenced in the county of Ontario, and proposals are issued for the eighth.
TANNER, VALLANCE, KEARNY & Co. engravers, Philadelphia, propose to pub
In London, an English translation is in preparation of" The History and Process of Lithography, or the Art of Printing Designs from Stone, by the Inventor, Mr. ALVIS SENNEFELDER, of Munich, (Germany) illustrated with a series of specimens of Lithographic Art."
Dr. A. BROWN, Professor of Rhetorio in the University of Edinburgh, who was some time resident in the United States, has nearly ready for the press "a great work on the Physical, Moral, and Political History of America."
M. RENOUARD, Paris, has circulated a specimen of a new edition of Voltaire's Works, in 60 volumes 8vo. with 160 engravings.
A new volume of the Transactions of the Royal Academy of Sciences, Belles Lettres and Arts, of Pistoja, Italy, has recently appeared.
The first volume of ROSENMÜLLER'S Morgenland, &c. has lately been published at Leipsic. The East, Ancient and Modern, or Illustrations of Holy Scripture, derived from the Nature of the Country, the Conditions, Manners and Usages of the East.
JOHN WHITAKER, London, publishes in numbers, The Seraph; a Collection of Sacred Music, suitable to Public or Private Devotion. Consisting of the most celebrated Psalm and Hymn Tunes, with Selections from the Works of Handel, Haydn, Mozart, Pleyel, &c. &c. To which are added, many original Pieces.
FISCHER, of Schaffhausen, (Germany)