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A bicycle is a two wheeled vehicle driven by the riders feet pushing on cranks or pedals. A common misconception is that the earliest form of bicycle was the dandy-horse, which was pushed along by the rider's feet. However, while both the dandy-horse and the later bicycle are both velocipedes, the dandy-horse is not propelled by cranks.
The first bicycle was introduced to England from France in 1868, and comprised two solid wheels of equal size fitted to a frame, much like a modern bicycle in appearance, with a saddle fitted in the centre and propelled by cranks attached to the front wheel. This vehicle provided such a bumpy ride to the rider that it became popularly known as 'the bone-shaker'. Later came the Penny-Farthing with pedals fixed to the large front wheel which was made large to achieve high speeds. Later still, around 1895, came the safety bicycle with pedals driving the rear wheel by way of a chain, and the rider sitting upon a saddle set back from the front wheel so as to reduce the chances of falling forwards over the handlebars, from this developed the Raleigh bicycle design of 1900 which forms the basis of the modern bicycle. In 1888 the two-person tandem bicycle was invented.
In 1906 it was reported that speeds of 50 mph were attained on a bicycle. Around the same time, slightly earlier, the motorised bicycle (motorcycle or motorbike) was invented.
A typical bicycle is comprised of several parts. The principal and essential being: the frame, front forks, wheels, pedals, saddle, handlebars, chain and brakes. The largest part of the bicycle is the frame, and these vary in design depending upon the specialised intention of the bicycle.
A frame for a BMX bicycle being small, heavily braced and made of aluminium. The frame for BMX xyxling needs to be strong so as to endure the stresses of the bumpy ride, and the saddle low as competitors never sit down during a competition and as such they need space to sprint and jump with ease.
Cross-Country cycle frames are generally made of aluminium and carbon-fibre so as to be light weight. They are relatively small frames to allow quick and easy mounting and dismounting off road, and strong to endure off-road bumpy conditions. The smaller frames are often compensated for by having a longer seat post to allow a normal height saddle position.
The cycle speedway bicycle frame is designed primarily for strength, and as such is typically made from steel or aluminium.
Road racing bicycle frames are designed to be light and stiff. Traditionally they ewre made of steel, but by the start of the 21st century carbon fibre was being used for the more expensive models as this offered the same stiffness at reduced weight. The design of the tubes also developed over time, tubes becoming of a larger diameter, but thinner walls, to allow the same stiffness with reduced weight.
Bicycles are fitted with various types of brake, the most popular being the calliper, cantilever, hydraulic or disc and the V brake. The most common form of brake found on leisure bicycles, is that form used also on road racing bicycles. The calliper brake. Calliper brakes are a very efficient means of rim braking and basically comprise two blocks of rubber or plastic which are squeezed onto the wheel rim when the brake lever is squeezed by the ride.
Cantilever brakes operate on the same principal as calliper brakes, but are of a slightly different design at the wheel end, offering increased clearance between the tyre and the brake pads and as such are frequently employed for cyclo-cross bicycles and mountain bikes.
The most efficient form of rim brake is the V brake. The V brake also offers the most clearance of any rim braking system, and is most often found on mountain bikes.
Hydraulic or disc brakes are the most efficient and powerful form of bicycle brake. They use the wheel hub to brake, rather than the rim. Disc brakes offer the most clearance, and as such are used on mountain bikes, but are also expensive to fit and maintain.
Bicycle wheels are generally of one of three types. The most common and traitional bicycle wheel is the spoked wheel, comprising a rim connected to the central bub by a series of thin metal rods known as spokes. Spoked wheels are light in weight. Less common than spoked wheels, but offering greater strength and durability at the expense of weight are mag wheels which comprise a rim attached to the hub by a few, thick solid plastic bars. Solid wheels, also known as disc wheels, are made from composite material or carbon fibre are very strong, stiff, aerodynamic and very expensive. They are rarely used except as rear wheels in time-trialing and track racing.
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The coconut cup was a drinking vessel first seen in Britain around the 13th century, and used by the rich who preferred them to the more 'common' mazer-bowl. Coconut cups were made from a coconut shell, mounted on a Gothic silver mount and mounted with silver at the rim. Similar vessels were also made from ostrich eggs (then called griffin's eggs).
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Farriery is the art of horse-shoeing. It consists in the attachment of a rim of iron, by means of nails, to the lower border of the horse's hoof, in order to prevent its excessive wear.
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A Ferris wheel is an amusement park ride consisting of a large upright wheel rotating on a fixed stand and having suspended around its rim chairs, or capsules in which riders sit. These chairs or capsules are freely suspended so that they remain upright as the wheel rotates. The Ferris wheel was named after the 19th century American engineer G W G Ferris. The largest Ferris wheel is the London Eye on London's embankment which was erected for the millennium celebrations.
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Mazer-bowls, also known simply as a mazer or a mazer cup, we drinking vessels first introduced to Britain in the 14th century. They were a bowl made of spotted maple wood, whence their name, and normally mounted in latten metal, silver or silver-gilt, with a wide band around the rim. Often a circular medallion was mounted in the bottom of the bowl, and the whole was finished by a foot or set upon a baluster. By the end of the 16th century were the most popular drinking vessels in Britain.
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An alligator is a genus of crocodilian reptile of the family Alligatoridae. They differ from the true crocodiles in having a shorter and flatter head, in having cavities or pits in the upper jaw, into which the long canine teeth of the under jaw fit, and in having the feet much less webbed. Their habits are less perfectly aquatic. They are confined to the warmer parts of America, where they frequent swamps and marshes, and may be seen basking on the dry ground during the day in the heat of the sun. They are most active during the night, when they make a loud bellowing. The largest of these animals grow to the length of about six metres. They are covered by a dense armour of horny scales, and have a huge mouth, armed with strong, conical teeth. They swim with wonderful celerity, impelled by their long, laterally-compressed, and powerful tails. On land their motions are proportionally slow and embarrassed because of the length and un-wieldiness of their bodies and the shortness of their limbs.
Alligators feed on fish, and any small animals or carrion, and sometimes catch pigs on the shore, or dogs which are swimming. They even sometimes make man their prey. In winter they burrow in the mud of swamps and marshes, lying torpid until the warm weather. The female lays a great number of eggs, which are deposited in the sand or mud, and left to be hatched by the heat of the sun, but the mother alligator is very attentive to her young. The most fierce and dangerous species is that found in the southern parts of the United States Alligator Lucius, having the snout a little turned up, slightly resembling that of the pike. The alligators of South America are there very often called Caymans. Alligator sclerops is known also as the Spectacled Cayman, from the prominent bony rim surrounding the orbit of each eye. The flesh of the alligator is sometimes eaten. Among the fossils of the south of England are remains of a true alligator Alligator Hantoniensis in the Eocene beds of the Hampshire basin.
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The helix rings the uppermost portion of the ear and forms the rim of the outer ear. The inner curved prominence that lies parallel to the helix is the antihelix. It also borders the back and top of the concha. The helix and antihelix are composed of cartilage. The outer ear is composed of a single piece of cartilage, with the exception of the lobule.
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The tympanic membrane (ear drum) is a thin semitransparent, oval-shaped membrane, set in the auditory canal. It has a stiff rim and a concave outer surface. It is quite small and is often called the 'ear drum' because it resembles the skin stretched across a drum. Sounds in the ear canal cause the tympanic membrane to vibrate with complex patterns. It is attached to the malleus, the first of the middle ear's three bones. The tympanic membrane's vibrations move the malleus, which in turn moves the incus. The incus then moves the stapes which is attached to the oval window.
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The zygomatic or malar bones form the cheek and the lower, outside rim of the orbits. The temporal process of the zygomatic bone curves around the side of the skull to meet the zygomatic process of the temporal bone, forming the zygomatic arch. The upper, frontal part of the zygomatic bone, forming the outer rim of the orbit and meeting the frontal bone, is called the frontal process, while the orbital surface defines the smooth, lower and outer wall of the orbital cavity. Each zygomatic bone features a zygomaticofacial foramen, or opening, into the bone near the lower corner of the orbit.
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The deringer (also spelt derringer) was a pocket pistol invented by Henry Deringer of Philadelphia in the mid-19th century. The original models were single barrelled percussion muzzle loaders with a rifled barrel. In 1861 Daniel Moore patented a .41 inch calibre rim-fire cartridge model.
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The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
©1993 - 2009 The Probert Encyclopaedia
Southampton, United Kingdom
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