Paddle wheel

“ Its adaptability for certain classes of work has given the paddle-wheel a long lease of life. Paddles are peculiarly suitable for certain conditions, such as smooth waters and shallow rivers, where speed and light draught combined with considerable carrying power are essential. ”

“ They were traveling about as fast as a lame man could walk, but there was an exhilarating throb to the engine, and a cheerful slap-slap to the paddle-wheel, and the river went past them instead of taking them with it, and by shutting their eyes for five minutes and then opening them they could see that they were actually gaining on the scenery. ”

“ A.--In all paddle vessels, whatever be their subordinate characteristics, a great shaft of wrought iron, s, turned round by the engine, has to be carried from side to side of the vessel, on which shaft are fixed the paddle wheels. The paddle wheels may either be formed with fixed float boards for engaging the water, like the boards of a common undershot water wheel, or they may be formed with feathering float boards as they are termed, which is float boards movable on a centre, and so governed by appropriate mechanism that they enter and leave the water in a nearly vertical position. ”

“ That which retains the paddle-wheel in favor to-day, and renders it a necessity in spite of argument or prejudice, is the fact that the screw requires that the draft of the ship shall not be less than its own diameter, whereas in the largest paddle boats a dip of wheel of six feet is generally sufficient. Hence it is that nearly all fast steamers plying on rivers or shallow estuaries, and channel steamers running to ports where there is little water when the tide is low, are of necessity paddle-wheel. ”

“ A Simple Paddle-wheel The simple paddle-wheel, as shown at Fig. 1, is made from an axle three inches square, four spokes, and four boards. For a wheel of medium size that will develop about one-eighth of a horse-power the axle should be four feet long. One end is rounded for a distance of four inches as shown at A, and with bit and chisel two mortises are cut in opposite directions as shown at A. These holes are one inch and a quarter wide and three inches long. Into them the spokes are driven and held with screws or iron pins. ”

“ To impel a vessel by this means, two paddle wheels, like those used in an under-shot water-wheel, are connected by means of a long axis and crank, with the working beam of the steam-engine; and if this motion is not found sufficiently rapid, a wheel and pinion are added, which, although it decreases the effective power of the engine, yet increases the velocity of the paddle wheels. ”

“ A peculiarity of some of the larger paddle-wheels in use in America is that they are not only of much greater size than those in use in Great Britain in proportion to the size of the boat, but they have a proportionately less immersion and the wheel is constructed in a very different fashion. The floats, instead of being of one piece, as here, are constructed of three narrow fixed strips, two of which are on the same radius but have a space between them equal to the breadth of the third strip, which is placed a few inches behind the vacant space. ”

“ The Success consists of two sections, to be disconnected for passing the locks, with paddle-wheel machinery at the bow. Her wheel, inside of the paddles, is a drum or cylinder, filled with cork, to be buoyant, and the hull has an easy, scow bow, for the water to pass under the boat. Practically, the large drum makes her a horizontal, cylindrical-bowed boat, and she mechanically throws the water therefrom against the scow-shaped bow, and so that the cylinder displacement with the mechanical currents, and the scow-bow displacement, combine to make her very slow. ”

“ The condensers were of the jet type, and there were two air-pumps, which were driven by a single crank in the middle of the paddle shaft. The paddle-wheels were tremendous, weighing ninety tons each, and measuring fifty-six feet in diameter. But the Great Eastern amply proved how unsuitable the paddle-wheel was for ocean work. Every time the big monster rolled in a bad sea a great strain was put on the machinery; these vast projections, too, offered not merely increased windage and accentuated the ship’s general unwieldiness, but afforded a fine target for the Atlantic waves to smash against. ”

“ He lived to see the paddle-wheel grow in importance and estimation as a means of propulsion only in turn to be supplanted by the screw-propeller, which gradually increased in engineering favor from the days of its obscure infancy until it became the only means employed for the propulsion of ships navigating the high seas, while it had become a most serious rival to the paddle-wheel even for the purposes of interior and shallow-water navigation,--long a field considered as peculiarly suited to the paddle-wheel and to the engines adapted to its operation. ”

“ The race of water from the wheels past the ship being at a high velocity, and raised above the normal level, causes a resistance to the ship beyond that due to her passage through the water, as in the case of a screw ship. On the other hand, the paddle boat is more readily got into motion and her speed more rapidly arrested than is the case with the screw steamer; and it is claimed for the paddle-wheel—although the foundation for such a claim is rather nebulous—that when the engines are working at full speed the ship is prevented from the excessive rolling observable with a screw vessel. ”

“ When the heavy gong sounds, and the rumble of the paddle-wheels stops, and the boat glides silently over the water, it is then that the pilot and his engineer are on the alert—one with his hand on the wheel, moving it this way and that, and the other with his hand on the lever bar, ready to back water or go ahead, according to his signals. ”

“ The flywheel has a shaft fitted with two gears, and is driven through idler gears from gears on the paddle-wheel shaft; it turns at about twice the speed of the paddle wheel. No other pumps or fittings are shown in the engine hull, although manual pumps were probably fitted to fill and empty the boilers. ”

“ Then we cut sixteen paddles of the form shown in Fig. 257. Eight of these were 12 inches long, and the rest measured 18 inches. A slot 3 inches deep was cut in each paddle of just the right width to slip over the tie boards. The shorter paddles were fastened on just back of the spokes, and the rest were secured half-way between each spoke. The paddles were braced by stretching a wire from one to another all the way around the wheel. ”

“ Here modern genius and skill, as in a thousand other instances, substitutes mechanical for manual labour. The modern paddle, in its revolutions, performs exactly the same duty as the oars of the ancients in their simultaneous movements, and the well-trained crews of the Grecian and Roman galleys in their action at the oars were, so far as is traceable, almost as regular as the beat of the paddle-wheel. ”

“ In low water no one man ever thought of standing a watch alone at the wheel, and at times she would run away with two men at the wheel. She was short, "stubby", and narrow; and when she smelt a reef she would, unless very carefully handled, under a slow bell, run away from it, often with one paddle wheel backing while the other was coming ahead, and the rudder standing squarely across the stern. ”

“ At the best it is simply a question of the relative influence in the introduction, improvement, and practical application of what was the common property of the engineering practice of the day.
In 1833, or at the period now under consideration, however, the paddle-wheel was the recognized instrument of marine propulsion. Since the beginning of the century it had been growing in use with the gradual growth in the application of steam, and at this time it held the field alone. ”

“ Above the tapers is a horizontal paddle-wheel, which is set revolving by the current of air caused by the flame, and from the wheel silk threads are led to a series of little automaton figures of men, women, birds, beasts, etc., all of which move their arms, legs, and wings as the wheel runs round. ”

“ The deepest would be selected, and if only two or three more inches of water were needed, the boat would be run up as far as it could go, the crew would fix the two great spars with their shoes against the bottom, slanting downstream, set the steam capstans drawing on their ropes, and then reverse the paddle wheel. The turning of the great wheel would force water under the hull while the spars pushed backward and, raising a platform of water around her and taking it with her, she would slide over the shallow place and go on about her business. ”

“ The person in front helps to propel the boat with hand levers which are connected with rods to sprocket wheels on each side of the platform. The occupant of the rear seat contributes his part of the power with his feet on pedals of the shaft that carries the sprocket wheels. This shaft and sprocket wheels drive the paddle wheel by side chains of the bicycle kind. ”

“ That lies in wait to make a silent rush,
And there was something in her like a thrush,
For she had paddle-wheels, each like a wing.
She had a long hornet stern that seemed to hold a sting.
Sometimes her paddles slowly turned,
For they kept steam up, waiting for a gale.
It seemed as if the slim boat chafed and yearned
To go hell-tearing under steam and sail.
The oily water churned
And made a slap-slap to the paddles' stroke ”

“ The propelling power is a large diameter wheel at the stern of the boat, the full width of the vessel, resembling the undershot wheel of a mill, and driven by two cylinders, one on either side. The floats of this wheel are but 8 to 10 inches in the water when light, and 30 inches when loaded, and do not therefore produce those destructive currents which come from the screw or paddle steamer. ”

“ Again, even when the immersion of the vessel is such as to give the best advantage to the paddle-wheels, that advantage is lost whenever a side-wind inclines the ship to one side, or whenever by the action of the waves the immersion of the paddles is changed by excess or defect. ”

“ The commotion in the water made by paddle-wheels, which is an objection to their use in narrow rivers, is avoided by screw propellers, which being immersed under the water, make little agitation on the surface, and the ships move along without any apparent impelling power. ”

“ Only a few boys have ponds of their own, in a pasture, perhaps. But there are miniature lakes in our city parks, pools at our summer camps, and old water holes in the woods; if all of these fail, a boy can still sail his ships on the bathtub sea. A simple side-wheeler, built of wood, is shown in the sketch. It winds up with a crank and runs 15 to 20 ft. A float is made by pointing the ends of a thick board, the dimensions of which are given in Fig. 1. On this the paddle-wheel frame is nailed, as shown in the top view, Fig. ”

“ If a steamboat 100 feet long, of 5 feet beam and 4 feet draught, be provided with one set of common side paddle wheels, and power enough to run it at the rate of 10 knots per hour, would two sets of side wheels, with the power doubled and the revolutions of the wheels doubled, double the speed of the boat? ”

“ Cut out of a seven-eighths of an inch board a hull like that seen in the illustration, and make the hole for the pivot at the middle point between bow and stern; bore another hole just aft of this for the axle of the paddle-wheels. Out of thin wood cut two circular disks for these wheels, and dovetail the paddles into their edges as seen in Fig. 2. Next cut out two half circles of your thin wood for paddle-boxes, and bore a hole in each for the axle of the wheels. These are to shield the upper half of the wheels from the wind. Now take a piece of tin, in shape like Fig. ”

“ With what force must these wooden paddles strike the waves which are now gently breaking over them! what a boiling of water when this powerful engine strikes it blow after blow! what a thundering noise engulfed in this paddle-box cavern! when the "Great Eastern" goes at full speed, under the pressure of wheels measuring fifty-three feet in diameter and 166 in circumference, weighing ninety tons, and making eleven revolutions a minute. ”

“ To plunge the bare arms to the elbow into the river as you go, and let the cool water curl up to the biceps; to feel the soft breeze on bare head and neck; to be far from the busy crowds in the cities, with all the senses awake to new and fascinating objects—the swirl of rapid water, the brown and yellow stones on the bottom of the river, the large, free movements of clouds, the strange flowers on the bank; to grip the paddle with an agreeable sense of power in shoulder and hand; to brace the feet strongly against the foot-rest and feel the canoe spring with the elastic force of the stroke ”

“ The primitive wooden paddle, imitating the form and doing the work of the flat hand or foot, is well known to savages, who mostly use the single paddle with a blade or shovel end; the double-ended paddle, such as our canoeists have borrowed from the Esquimaux, is a peculiar improved form. The paddle used free-handed to dig or sweep at the water, is best suited to the narrow bark-canoe or hollowed trunk, but for larger craft it is a rude contrivance as compared with the civilized oar, which is a lever pulled against a fulcrum so as to use more of the rower’s force, and in a steadier pull. ”