Catherine wheel

“ And some are fifth wheels like myself—neither old nor self-effacing, neither middle-aged nor useful, but simply expensive to keep painted, and very hungry for the road. It may be only a matter of time, however, when I shall be middle-aged and useful, and later old and self-effacing; when I shall stay and take care of the children, and go upstairs early when the young people are having a party.
A young technical college graduate told me once, to comfort me, I suppose, that a fifth wheel is considered by a carriage-maker a very important part of a wagon. ”

“ The rim of iron with which the wheel is to be bound, is made in the first instance of a diameter somewhat less than that of the wheel; but being raised by the application of fire to a very high temperature, its volume receives such an increase, that it will be sufficient to embrace and surround the wheel. When placed upon the wheel it is cooled, and suddenly contracting its dimensions, binds the parts of the wheel firmly together, and becomes securely seated in its place upon the fellies. ”

“ The racing carts, decorated with many colors, lined the track. The “trots” were exciting, but the free-for-all race was the climax of the celebration.
[52]
TUB CART Natural color varnish; metal-rimmed ties. Trimmed in brown leather.
Each of the Webb children in turn learned to drive in this little cart dating from about 1883 and made to Dr. Webb’s specifications by a local wheelwright. Wheelwrights often made entire vehicles and served as village carpenters.
Wheel-making consisted of several processes—the hub was first turned by hand lathe and then mortised to take the spokes. ”

“ Let A B and D C, fig. 179., be two wheels revolving on pivots P Q with as little friction as possible, and so placed that the axle O of a third wheel E F may rest between their edges. As the wheel E F revolves, the axle O, instead of grinding its surface on the surface on which it presses, carries that surface with it, causing the wheels A B, C D, to revolve.
In wheel carriages, the roughness of the road is more easily overcome by large wheels than by small ones. ”

“ If carriages had always to move along perfectly smooth roads, such as a tramway of wood, iron, or stone, the use of wheels in overcoming friction would be their sole utility, and the height of the wheels would be of small consequence. But as carriages are drawn along roads with loose stones and uneven surfaces, wheels are further useful in mounting over these obstacles, and it is plain that a high wheel does this more easily than a low one. ”

“ Again, the long spoke acts as a longer lever, the point of draught being the axle, which is higher from the ground in the higher wheel, and again assists in overcoming the obstacle, as the angle of incidence is so much less.
To learn that the leverage power of a high wheel is very great we need only consider the advantages gained by a large wheel in locomotives and in bicycles. In practice we find that wheels from 4 feet to 5 feet are sufficient for large carriages, and from 3 feet upwards for ordinary vehicles. ”

“ Wheels, we have seen, may be made of different dimensions, according to the purpose to which they are applied. The most common are three or four feet in diameter, with a nave of hard wood, and spokes of light wood. They are sometimes surmounted with a fell, and frequently by seve [419] ral concentric hoops, placed at different distances from each other.
Wheels, in general, are furnished with cases, and various decorations. Some have two, three, four, and more fires; but, if they are finished too much, the weight they thus acquire would retard the velocity of the wheel. ”

“ In addition to the friction of the rolling motion on the road, they have, it is true, the friction of the axle in the nave; but, on the other hand, they are free from the friction of the rollers with the under surface of the load, or the carriage in which the load is transported. The270 advantages of wheel carriages in diminishing the effects of friction is sometimes attributed to the slowness with which that axle moves within the box, compared with the rate at which the wheel moves over the road ”

“ The rider, therefore, pedalled by pushing the levers down alternately and releasing the pressure at the end of the strokes. The Facile was followed at a later date by the Geared Facile, which was the same design as the Facile and had the same lever motion for pedalling, but included a sun and planet gear on the hub. Briefly, this consisted of a large toothed wheel on the axle and a crank extending beyond the edge of the wheel. Working in a bearing on the crank end was a small planet pinion, or toothed wheel, which meshed with the larger toothed wheel. ”

“ Pressing this invention to the ultimate produced a spoked wheel. The Egyptians used a six-spoked chariot wheel thousands of years before Ezekiel's time, and the Greeks and others had four-spoke models. This was quite an invention and in addition to its useful aspects, it produced some rather unusual, even magical side-effects. As every child knows, if you turn your tricycle upside-down and spin the wheel, the spokes seem to vanish. All that can be seen is the rim and the parts of the hub near the center of rotation. No matter what shape the hub actually is, it too looks round like a wheel. ”

“ Wheels thus proportioned, revolving in exactly the same time, might be all placed on one axle, and would partake of one common motion, or, what is to the same effect, several grooves might be cut upon the face of one solid wheel, with diameters in the proportion of the odd numbers 1, 3, and 5, &c., for the lower pulley, and corresponding grooves on the face of another solid wheel represented by the even numbers 2, 4, 6, &c., for the upper pulley. ”

“ In the correct position the wheelman has his arms a trifle bent, at the elbow, so that when he goes over any unevenness in the road his arms give, and he avoids the shaking of his whole body by the jounce, to say nothing of the certainty of giving his wheel an unpleasant shaking up.
In the most modern wheels the position of the rider is almost that of a pedestrian—that is, the pedals are almost under the saddle, so that he treads directly up and down. ”

“ If you keep the present dish, you must have a narrow wheel, or it is rubbing; but if it is a straight axle, it ought to be as wide as that where there is no more friction, and then the wide wheel will not do half the mischief that the coach-wheel does. The present stage coach-wheel will do a great deal more mischief, working as it does, than if it had been perpendicular. ”

“ The objections to the high bicycle were many, and among its chief drawbacks were that owing to the disparity in wheel diameters and the small weight of the backbone and trailing wheel, also to the rider’s position practically over the centre of the wheel, if the large front wheel hit a brick or large stone on the road, and the rider was unprepared, the sudden check to the wheel usually threw him over the handlebar. ”

“ Considering that the railway-carriage builder gives up the coach-wheel principle, and returns to the primitive construction of the pair of wheels fixed to the axle turning in bearings, we see that our ordinary carriage-wheels turning independently on their axles are best suited to comparatively narrow wheels, and to smooth ground or made roads. Here they give greater lightness and speed, and especially have the advantage of easily changing direction and turning, which in the old block-wheel cart can only be done by gradually slewing round in a wide circuit. ”

“ Pressure on the pedal caused the planet wheel to travel around the larger sun wheel and the road wheel was geared up to the extent of the added diameter of the planet wheel. Thus, if the planet wheel were one-fourth the size of the sun wheel, it geared up the road wheel of 45 ins. ”

“ In many cases it is easier to roll a thing than it is to drag it. This fact led to another step in the development of the carriage; it led from the cart without wheels to a cart with a wheel—a most important step in the history of inventions. The first wheeled cart was simply a log from each end of which projected an axle (Fig. 5) . The axle fitted in the holes of a frame upon which the body of the cart was placed and to which the horse or the ox was attached. As the cart moved along, wheel (log and axle) turned together. ”

“ Portugal the old classic bullock-cart on this principle is still to be seen, and it has been reasonably guessed that such carts tell the story how wheel-carriages came to be invented. Rollers were early used, on which a block of stone or other heavy weight was trundled. Suppose such a roller made of a smoothed tree-trunk to be improved by cutting the middle part smaller, so that it became an axle and pair of broad wheels in one piece, then by making this axle work underneath the rudest framework, the simplest imaginable wheel-carriage is made. ”

“ Each of the four wheels has a different diameter. Their two axles converge toward the center of the circular track upon which each horse moves, and the axis inclines toward the center.
Each pair of wheels, therefore, constitutes a true rolling cone, whose apex passes through the central point of the track situated upon the horizontal rolling plane. The inequality of the wheels naturally makes it necessary to employ but a single driving wheel, and to mount the four wheels loose upon the axles. ”

“ We have now arrived at the stage when a high bicycle was regarded as dangerous, and, if the front wheel were too small, it detracted from the rider’s speed owing to the shorter distance covered by each turn of the wheel. What was the next move? The engineer’s mind turned towards a method of gearing by cogs or chains, by which one turn of the crank axle would cause the driven wheel to turn more than once. That is where we get our method of describing the ratio of gearing between the crank and the wheel of a modern safety bicycle. ”

“ The shaft-gearing of these spur-wheels consists of impact roller motions, so that the crank centrally on the shaft, within easy reach of the operator upon the seat and between the driving-wheels, may be effectually operated by the hand, and a lever from the guide-wheel is designed to be in such a position as to be within easy reach of the operator’s feet forwardly, so that no difficulty will be encountered, all of which will now be fully set forth. ”

“ It is evident that one of the greatest, if not the very greatest, of the requirements of a practical road wheel, or a man-motor carriage, is that the power of the rider shall be transmitted to the said wheel in the most direct manner possible; that is, by causing the strain to come upon the muscles in such a way that these muscles shall be placed in the best possible position to overcome such strain, and to take advantage of such conditions as nature has already provided for, in training our muscles to the work we have had to do under the old régime, without the wheel. ”

“ The truck wheels, of the hollow spoke pattern, are cast iron with chilled treads. They were made by Asa Whitney, one of the leading car-wheel manufacturers in this country, whose extensive plant was located in Philadelphia. Made under Whitney’s patent of 1866, these wheels may well have been added to the Pioneer during the 1871 rebuilding. Railroad wheels were not cast from ordinary cast iron, which was too weak and brittle to stand the severe service for which they were intended, but from a high-quality cast iron similar to that used for cannons. ”

“ A revolving body that is not exactly balanced runs unequally, and transmits a tremor to anything with which it may be in contact. Turn a cycle upside down and revolve the driving-wheel rapidly by means of the pedal. The whole machine soon begins to tremble violently, and dance up and down on the saddle springs, because one part of the wheel is heavier than the rest, the mere weight of the air-valve being sufficient to disturb the balance. Now consider what happens in the engine-room of high-powered vessels. ”

“ A skilled rider invariably adopts this position when free wheeling on rough roads and also instinctively falls into it when pedalling forward, with either a fixed or free wheel; with the former he slackens speed and bears his weight on the rising pedals, so raising his weight out of the saddle ”

“ John Green or of his partner was heard of, and his patent coaches found few if any purchasers.
The other contrivance was a primitive form of gear invented by one James Rowe. In 1727 this Rowe wrote a book—not, however, published until 1734—called All Sorts of Wheel Carriage, Improved. This was a small tract “wherein is plainly made to appear, that a much less than the usual Draught of Horses, etc., will be required, in Waggons, Carts, Coaches, and all other Wheel Vehicles” by the application of small “friction wheels and pulleys.” ”

“ This greater outlet area is obtained by splaying the wheel, as shown in the section (fig. 199) .
§ 200. Pelton Wheel.—In the mining district of California about 1860 simple impulse wheels were used, termed hurdy-gurdy wheels. The wheels rotated in a vertical plane, being supported on a horizontal axis. Round the circumference were fixed flat vanes which were struck normally by a jet from a nozzle of size varying with the head and quantity of water. Such wheels have in fact long been used. They are not efficient, but they are very simply constructed. ”

“ The roads are bad, but they will not account for those carts. The little front wheels are a stroke of mechanical ineptitude positively amounting to genius, and when they are replaced by a single wheel, and the whole affair resembles a huge tricycle, one instinctively looks round for a Dinosaur. Time after time we met them stuck in the mud or partially overturned, but the drivers seemed in no way disconcerted ”

“ In the Ammerland, a district of Oldenburg, you may sometimes see an old cart-wheel fixed over the principal door or on the gable of a house; it serves as a charm against witchcraft and is especially intended to protect the cattle as they are driven out and in. See L. Strackerjan, Aberglaube und Sagen aus dem Herzogthum Oldenburg (Oldenburg, 1867) , i. p. 357, § 236. Can this use of a wheel as a talisman against witchcraft be derived from the practice of rolling fiery wheels down hill for a similar purpose? ”