From 7000 BC

The sledge: 7000-4000 BC

From the beginning of human history people have dragged any load too heavy to be carried. But large objects are often of awkward shape and texture, liable to snag on any roughness in the ground. The natural solution is to move them on a platform with smooth runners - a sledge.

Wooden sledges are first known, by at least 7000 BC, among communities living by hunting and fishing in northern Europe, on the fringes of the Arctic. It is possible that they use dogs to pull them, but the technological advance is valuable even without animal power. On icy ground a man can move a heavy load on a sledge with relatively little effort.

The Domestication of cattle, and more particularly the discovery that a castrated bull becomes the docile but very powerful ox, means that humans can transport heavier loads than before. This is done at first on sledges, which slither adequately over the dry grass of the steppes of southern Russia and on the parched earth of Mesopotamia. In both regions ox-drawn sledges are in use by the 4th millennium BC.

The natural next stage is the addition of wheels.

The wagon: 3000 BC

A wagon gets stuck in the mud, more than 5000 years ago, near what is now Zürich. It has two pairs of solid wooden Wheels, each attached to an axle which turns with them. The wagon is massively heavy (perhaps about two thirds of a ton, or 700 kg) and it is irretrievably stuck. It stays where it is. It is now one of the earliest known examples of wheeled transport.

Whether first developed as an 'invention' in one place, or re-invented in several, Wheels seem to have evolved as a natural solution to the problem of transport in areas where both oxen and wood are available. By 2000 BC heavy wheeled transport is in use in a region stretching from northern Europe to western Persia and Mesopotamia.

The Wheels of the first wagons are made either from a single piece of wood or from three joined planks; sometimes they turn on the axle, sometimes with it. Speed is not the main characteristic of such a vehicle, as anyone will know who has seen bullock carts on the farm roads of India today. Even so, during the third millennium BC wagons acquire a regal status in addition to their practical uses. They can only transport the king on his throne at about two miles per hour in a public ceremony, but royal tombs reveal that both wagon and oxen are valued enough to be required in the next world.

For even greater glamour, and far greater speed, two new elements are needed - the horse and a spoked wheel.

Horse and chariot: from 2000 BC

The horse is available in Mesopotamia by about 2000 BC. Not much later a two-wheeled chariot is developed. Its superstructure is made of a light wood, and its wheels are not solid; their rims are of bent wood, held in place by spokes. A horse can pull a chariot at a trot at up to 8 miles an hour - and at a gallop twice as fast.

Here is a vehicle in which a ruler or noble can cut a fine ceremonial dash. There are chariots among the treasures in the Tomb of tutankhamen. The wheels are stacked separately, not only because of the cramped space in the tomb. They are so delicate that the weight of a stationary chariot will distort their rims.

In subsequent centuries, up to relatively recent times, travel improvements are mainly limited to transport on the sea. They are the result of larger Ships (which can venture further afield) and of better methods of Navigation.

On land one large new beast of burden is domesticated - the Camel. But the main improvement in classical times derives from the construction of Roads, first in the Persian and then in the Roman empire.

6th century BC - 15th century AD

The great canal of Darius I: 6th century BC

The cutting of canals for irrigation has been an essential part of the civilization of Mesopotamia, controlling the water of the Euphrates and the Tigris. Several canals link the two rivers, and small boats use these waterways. But the world's first canal created purely for water transport is an incomparably more ambitious affair.

Between about 520 and 510 BC the Persian emperor, Darius i, invests heavily in the economy of his newly conquered province of Egypt. He builds a canal linking the Nile and the Red Sea. Its access to the sea is close to modern Ismailia, which much later becomes the terminus of another great waterway, the Suez canal.

Roman roads: 2nd century BC - 2nd century AD

The great network of Roman roads, the arterial system of the empire, is constructed largely by the soldiers of the legions, often with the assistance of prisoners of war or slave labour. The amount of labour involved is vast, for these highways are elaborate technological undertakings.

The average width of a Roman road is about 10 yards. Below the paved surface the fabric extends to a depth of 4 or 5 feet in a succession of carefully constructed layers.

First a trench is excavated. Its bottom is rammed hard, and if necessary is strengthened by driving in piles. Then four successive layers are constructed, each a foot or more thick. The first is of masonry, laid in cement or clay. Above this is a course of concrete, then gravel and cement. Finally the top layer is laid in dressed stones, sloping away in a pronounced camber from the centre.

The designers of the Roman roads are single-minded. Paying scant attention to the demands of contours, and having few property rights to consider, their mission is to drive the road straight ahead. The legions will march far in the empire, but they will take the shortest route.

Part of the purpose of the Roman roads is speed of communication, so there are posthouses with fresh horses every 10 miles along the route and lodgings for travellers every 25 miles. By the 2nd century AD the network spreads all round the Mediterranean and throughout Europe up to the Danube, the Rhine and northern England, amounting in all to some 50,000 miles. This far outdoes even the very impressive achievement of the Persian roads . Travellers on foot or horseback have rarely been so well provided for.

For haulage purposes these roads are less satisfactory, because the straight line results in some very steep hills. Anyone with a wagon and horse would prefer an attitude less severe than that of the Roman road engineer.

The Grand Canal: 3rd century BC - 13th century AD

The Chinese (the greatest early builders of canals) undertake several major projects from the 3rd century BC onwards. These waterways combine the functions of irrigation and transport.

Over the centuries more and more such canals are constructed. Finally, in the Sui dynasty (7th century AD), vast armies of labourers are marshalled for the task of joining many existing waterways into the famous Grand Canal. Barges can now travel all the way from the Yangtze to the Yellow River, and then on up the Wei to the western capital at Xi'an.

Along this great Chinese thoroughfare the rice harvest of the Yangtze is conveyed to the centres of political power in the north.

From the 13th century there is a new northern capital. Kublai Khan establishes himself at Beijing, which becomes the capital of the Mongol or Yüan dynasty. The Mongols extend the Grand Canal all the way north to join Beijing's river at T'ien-ching.

Flash locks and pound locks: 10th - 15th century AD

From the very first construction of canals, some method is necessary to cope with differences in water level. The simplest solution is a weir, to hold up the water on the higher side, with a gap in the middle which can be opened to let a boat through. The removal of the barrier, however achieved, is inevitably followed by a sudden rush of water - carrying the vessel easily through in one direction, but making passage very difficult in the other. A primitive lock of this kind is known, for obvious reasons, as a flash lock.

The development of the more sophisiticated pound lock is traditionally credited to an engineer, Chiao Wei-yo, working on the great Chinese canal system in the 10th century AD.

It is said that Chiao is required to construct two flash locks on the Grand canal only about 200 yards apart. He realizes that he has created a pool which will be at the upper or lower level of the canal depending on which of the two barriers is open. Moreover the barrier separating patches of level water can be opened without the obstruction of water pressure.

The result is the pound lock, standard on all modern canals. The first in Europe is believed to have been built in the Netherlands in 1373 at Vreeswijk, where a canal from Utrecht joins the river Lek.

At this stage the barrier is a simple sluicegate which has to be raised and lowered like a guillotine. The process is laborious, and the water pressure against the flat surface requires a very strong construction to hold it.

The last missing piece in the design of the modern lock is the mitred lock gate. On this system each end of the lock is closed by a pair of wooden gates slightly too large to close in a normal flush position. They meet with mitred edges pointing in the direction of the higher water level. Water pressure holds them tightly together, until the level is the same on either side - at which point the gates can be easily pushed open.

The first lock with mitred gates is probably the one built in Milan in about 1500 to join two Canals of differing levels. Known as the San Marco lock, it is likely that its design is by Leonardo da Vinci. As his notebooks reveal, Leonardo is interested in all aspects of hydraulic engineering; and he is employed at this time by the duke of Milan.

From the 12th century Europeans have been busy constructing Canals, even with the primitive device of the flash lock. The mitre lock makes possible increasingly ambitious projects.

Junks and caravels: 12th - 15th century AD

In both east and west the centuries known in Europe as the late Middle Ages and early Renaissance see vast improvements in long-distance travel by sea. China is the pioneer. While Europeans are making ocean journeys in long narrow ships with a single square sail (the Longships of the Vikings), the Chinese are improving the design of the Junk.

From the 12th century junks grow in size, strengthened now by bulkheads. Soon they are steered and stabilized by an important innovation, the sternpost rudder. And they begin to be powered by sails on multiple masts.

These improvements make possible the expeditions carried out between 1405 and 1433 by the eunuch admiral Zheng he. He even reaches the east coast of Africa, a decade or two before the Portuguese exploration down the west coast of the continent.

The Portuguese successes depend, like the Chinese, on improvements in the design and construction of ships. The caravel is much smaller than the Junk, but it is better suited to sailing in violent oceans. With the caravel, travel becomes possible to any coast in the world other than the frozen Arctic and Antarctic. A caravel takes Magellan's crew on the first circumnavigation of the globe in 1519-22.

Inca roads: 15th century AD

The Inca roads, the arteries of an empire, amount in all to more than 14,000 miles. They are not paved, in the way of Roman roads, nor are they even much flattened - for this empire contains no wheeled vehicle nor any Horses.

The Incas rule over massively varied terrain, made up of large areas of jungle, desert and rugged highlands. Their roads are in effect paths, kept clear in these difficult conditions. Suspension bridges span small ravines, enabling runners to hurry unimpeded with a message - or caravans of llamas to make slower but steady progress with bales of raw materials and precious fabrics.

As in the ancient Persian empire and many others, runners are housed at short distances along the routes to provide a rapid relay service. But unlike similar routes in Asian empires, these roads transmit only verbal messages. The Incas have no writing. Their empire is administered like a vast game of Chinese whispers. No doubt most communication gets through in accurate form. But then perhaps long-distance messages in all early empires tend to be simple - instructions to fight, to return to base, to send stated amounts of men or materials, with sometimes news of a king's death or the identity of his successor.

Instead of writing, the local medium for recording simple information is an invention of the Andean civilizations - the quipu.

European canals: 12th - 17th century AD

In one area of Europe, the Netherlands, canal building is an integral part of economic development. The primary purpose is drainage; an efficient transport network is a welcome bonus. But in Italy, in the late 12th century, an ambitious canal is constructed without any subsidiary motive of drainage or even irrigation.

It is the Naviglio Grande, built between 1179 and 1209 to bring marble from near Lake Maggiore for the construction of the cathedral in Milan. The barges float down the river Ticino before diverting into the canal, which has a fall of 110 feet in its length of 31 miles. The next comparable project, a century later, is a canal with a different purpose - to improve trade.

From 1391 the Stecknitz canal is constructed southwards from the city of Lübeck. Its destination is the Elbe, which is reached early in the 15th century. The new waterway joins the Baltic to the North Sea.

This canal rises some 40 feet from Lübeck to the region of Möllner and then falls the same amount again to reach the Elbe, all in a distance of 36 miles. This must be about the limit which can be safely achieved with Flash locks. With Mitre locks, from the 16th century, anything is possible. And the most ambitious projects are undertaken in France.

The Briare canal, completed in 1642, joins the Seine to the Loire; at one point it has a staircase of six consecutive locks to cope with a descent of 65 feet over a short distance. Even more remarkable is the Canal du Midi, completed in 1681, which joins the Mediterranean to the Atlantic by means of 150 miles of man-made waterway linking the Aude and Garonne rivers. At one point this canal descends 206 feet in 32 miles; three aqueducts are constructed to carry it over rivers; a tunnel 180 yards long pierces through one patch of high ground.

The potential of canals is self-evident. It falls to Britain, in the next century, to construct the first integrated system of waterborne traffic.

16th - 18th century

Carriages: 17th century AD

Throughout the Middle Ages, when Europe's roads are little more than tracks, wheeled vehicles are used only for the laborious process of carting goods from place to place. When going on a journey, the able-bodied ride; the infirm are carried in a litter.

This changes in the 17th century, when there is some improvement in the paving of roads. Carriages are available for hire in the streets of London from 1605. By the second half of the century there are traffic jams. Samuel Pepys, conscious of rising in the world, considers it embarrassing in 1667 to be seen in London in a common hackney carriage which anyone can hire. The next year he happily acquires a coach and a liveried coachman of his own.

Coaches gradually become more comfortable. The most common design, developed in Germany in about 1660, is known as the berlin. The compartment for the travellers has the shape of a shallow U, with a protective roof above. There is a door on each side and the coach can seat four people, in pairs facing each other. The coachman, driving the horses, sits above the front wheels.

From 1680 glass windows keep out the weather, where previously there were only blinds. The first simple suspension, protecting the occupants against the bumps of the road, consists of leather straps on which the compartment hangs from the framework. The berlin introduces curved metal springs, which absorb the shocks more effectively.

A much lightier and racier two-wheeled vehicle, the gig, is introduced in Paris during the late 17th century. Relatively cheap, pulled by a single sprightly horse, driven by its owner and alarmingly easy to overturn, the gig is the first type of carriage to make driving an enjoyable activity.

At the other extreme from the gig, the more sedate citizen in 17th-century European capitals often uses human rather than animal power for short journeys. He hails a sedan chair and is carried, in elegant comfort behind glass windows, to his next destination. A sedan with wheels, known in Paris as a brouette, is pulled through the streets in the same way as a rickshaw in the east today.

The sedan chair soon goes out of fashion, but the carriages introduced in the 17th century evolve into the wide range of vehicles - many of them extremely beautiful - which are familiar on the streets of Europe and America until they are finally replaced in the 20th century by the car.

Among the best-known of such vehicles, featuring as they do in so many prints of the era, are the lumbering stage coach and its more effective successor, the mail coach.

Stagecoach and post chaise: 17th - 18th century AD

Travel between towns by public transport, in the 17th and 18th century, is a slow business. The stagecoach, a heavy and cumbersome carriage often without any form of springs, is introduced in Britain in 1640.

Up to eight of the more prosperous passengers can be packed inside a stagecoach. Second-class seats are available in a large open basket attached to the back. The least privileged travellers sit on the roof with the luggage, relying on a hand rail to prevent themselves slithering off.

This immensely unwieldly vehicle, drawn by either four or six horses, lurches along the rutted roads at an average speed of about four miles an hour. Danger from highwaymen is only one of many inconveniences on such a journey.

The noble and the rich, such as young men on their way through Europe on the Grand tour, travel in greater comfort - in private, and in well-sprung upholstered carriages. Their favoured vehicle is the post chaise, introduced in France in the early 18th century. Its name accurately suggests a pleasant seat, and an expectation of lively new horses at each post stage during the journey.

The post chaise is designed for just two passengers seated side by side and facing forwards - with a splendid view of the landscape through large front and side windows. The view is not obscured by a coachman, since the carriage is drawn by four horses with postilions riding on two of them. Driving in such a vehicle with Boswell in 1777, Samuel Johnson declares: 'If I had no duties, and no reference to futurity, I would spend my life in driving briskly in a post chaise with a pretty woman.'

Nevertheless the average traveller's experiences are fairly dismal during the 18th century. But some slight improvement is achieved in Britain after 1784, when the stagecoach begins to be replaced by the mail coach.

George Washington and the Conestoga wagon: AD 1755

A significant vehicle in the development of the American west makes its first appearance in 1755 when George Washington and edward braddock, his English commander, need transport for their baggage train. Preparing to move an army west through the Allegheny mountains to attack the French on the Ohio river, they acquire wagons built by German settlers in the Conestoga valley in west Pennsylvania.

Pulled by four or six horses and designed at first purely for freight, these wagons have the unusual feature of a floor dipping to a low point in the centre to avoid the cargo shifting on rough ground. For the same reason there are large broad wheels to cope with ruts and mud.

The Conestoga wagon has a curving roof of wooden hoops on which a white canvas cover is stretched for protection against sun or rain. When the vehicle is adapted in the 19th century to carry settlers travelling west, this white canvas top - reminiscent of a sail - gives the Conestoga wagon its new name of prairie schooner.

One of those driving the wagons on the ill-fated expedition of 1755 is a 21-year-old teamster, Daniel Boone. Twenty years later he leads the first wagon train taking settlers along the Wilderness road into new territory west of the Appalachians.

Bridgewater Canal: AD 1759-1761

In 1759 a young self-taught engineer, James Brindley, is invited to visit the duke of Bridgewater. The duke is interested in improving the market for the coal from a local mine which he owns. He believes his coal will find customers if he can get it more cheaply into Manchester. He wants Brindley to build him a canal with a series of locks to get barges down to the river Irwell, about three miles from the mine.

Brindley proposes a much bolder scheme, declared by some to be impossible but accepted by the duke. He will construct a more level canal, with less need for time-wasting locks. He will carry it on an aqudeuct over the Irwell on a straight line to the heart of Manchester, ten miles away.

On 17 July 1761 the first bargeload of coal is pulled along the completed canal. Brindley's aqueduct (replaced in 1894 by the present swing aqueduct) crosses the Irwell at Barton. The strange sight of a barge floating in a gutter high up in the air becomes one of the first great tourist attractions of the Industrial Revolution. The investment in this private canal rapidly pays off. The price of the duke's coal is halved in the Manchester market.

The Bridgewater canal is the first in Britain to run its entire length independently of any river. It is the start of the country's inland waterway systerm, for which Brindley himself will construct another 300 miles of canals.

Tracks and trails in America: AD 1775

In 1775 the first major effort is made by British colonists to build a road west through the Appalachians, so as to enable settlement of the land won from France (but not from its Indian inhabitants) in the French and indian war. Until this time the only way of travelling in the interior of the continent is either along rivers or on the narrow trails used by the Indians. These are adequate for horsemen and fur-trappers, but not for the wagons required if a settlement is to have a chance of becoming permanent.

One of the Indian trails, passing through the Cumberland Gap at the southwestern tip of Virginia, is known as the Warrior's Path. Daniel Boone, who has explored beyond the mountains, is commissioned in 1775 to turn this into a road.

With a party of axe-wielding companions Boone widens the trail to create the famous Wilderness Road, along which - over the next twenty-five years - some 200,000 settlers make their way into what becomes (in 1792) the state of Kentucky. Boone's wife and daughter are the first women to use the new road, in August 1775, joining him in establishing the settlement of Boonesboro on the south bank of the Kentucky river.

The Wilderness Road is the first example of American settlers blazing a trail (a blaze being a mark cut in the bark of a tree to show the way). The Sante fe trail and the Oregon trail will be famous 19th-century examples. But they are preceded by the National road.

Year of the balloon - hot air: AD 1783

Although hydrogen has been isolated by Cavendish in the 1760s, and shown to be fourteen times lighter than air, it is not until the early 1780s that Europe's inventors are suddenly gripped with a feverish interest in using the concept to achieve a form of flight. In 1781-2 scientists in both England and Switzerland fill soap bubbles with hydrogen and see them rise rapidly to the ceiling, but similar experiments with animal bladders prove disappointing.

In the event a more elementary idea, requiring none of the achievements of recent researches, provides the breakthrough.

In November 1782 a French manufacturer of paper, Joseph Montgolfier, wonders whether the simple fact of smoke rising might not be used to carry a balloon aloft. With his brother Etienne he begins making experiments. By June 1783 they are sufficiently confident to give a public demonstration in the town of Annonay.

They light a bonfire of straw and wool under a canvas and paper balloon with a diameter of about 35 feet. An astonished crowd sees the apparatus inflate and then drift into the sky. It rises, they estimate, to more than 3000 feet, stays in the air for ten minutes, and descends gently to earth 1500 yards away.

A report is immediately sent by the representatives of the local assembly to the Academy of Sciences in Paris. The news causes a sensation. The Montgolfiers are invited to the capital to demonstrate their invention.

Etienne makes the journey on their joint behalf and constructs a balloon to be launched at Versailles on September 19 in the presence of Louis XVI. This time the flying globe or aerostatic sphere (both are contemporary phrases) carries living passengers - a sheep, a cock and a duck. The trio travel more than two miles and land unharmed, except that the cock has been kicked by the sheep. The king, watching it all through his telescope, raises the Montgolfier family into the ranks of the nobility.

The final Montgolfier triumph takes place in November. A larger balloon is constructed, 46 feet in diameter, with a metal container (to hold the burning straw) hanging on chains just inside it. A basket, suspended below, is large enough to carry two people. Rigorous tests take place in a Paris garden. The tethered balloon, now bearing a passenger (Pilâtre de Rozier), is allowed to rise to successively greater heights.

At last, on November 21, all is considered ready. Four hands will be needed to stoke the fire with bundles of straw. Pilâtre is joined by a fellow passenger, the marquis d'Arlandes.

An excited crowd attempts to follow the path of the balloon as it rises and drifts away across Paris. In spite of alarming moments (such as their basket catching fire), the aeronauts make a successful flight, travelling about six miles in twenty-five minutes. They land safely, narrowly missing a windmill.

Those who have followed on horses are immediately on the scene. In the excitement Pilâtre's jacket, which he has taken off in the heat of the work, is torn to shreds and distributed as souvenirs. History has its first aviators.

Year of the balloon - hydrogen: AD 1783

News of the astonishing event at Annonay, in June 1783, prompts a Parisian physicist, Jacques Alexandre César Charles, to take serious steps to harness the property of hydrogen. He commissions from a silk merchant a balloon with a diameter of about 13 feet, and has it varnished with a gum solution.

To provide enough hydrogen Charles acquires 500 lb. of sulphuric acid and 1000 lb. of iron filings. The resulting gas is passed for four days through lead pipes into the slowly inflating balloon. At last, on August 27, a cannon is fired to signal the launch. The balloon rises rapidly to about 3000 feet in front of an ecstatic crowd on the Champ de Mars.

The contraption travels fifteen miles in forty-five minutes before springing a leak and crashing to the ground near a village. The first peasants on the scene, alarmed at the arrival of this monster from the sky, take the precaution of beating it until it seems undeniably dead.

Just as the hydrogen balloon is behind the hot-air version in the first ascent of any kind, so it is in the first manned ascent - but only by a very small margin. On December 1, ten days after the achievement of Pilâtre de rozier, Charles and a colleague rise into the air from the circular pond in front of the Tuileries. After a trouble-free journey of more than two hours, the aeronauts land about twenty-seven miles from Paris.

Charles's balloon, as befits that of a scientist, is more controllable than the Montgolfier version. It has a valve to release gas and descend, and it carries ballast which can be thrown overboard to rise again. The basket to carry the aeronauts is now a sturdy construction, looking like a small ship or gondola. And there is a Barometer on board to measure altitude.

After the first landing, Charles takes off alone for a second flight. The Barometer reveals that with the lighter load the balloon reaches the impressive height of about 10,000 feet, or two miles.

The hydrogen balloon soon prevails over the hot-air variety, because of its greater sophistication in an age when heat depends on burning bales of straw. Magnificent feats are achieved, beginning with a flight in 1785 across the English Channel by Jean Pierre Blanchard and an American doctor, John Jeffries. They throw out every loose item in the gondola, including their own clothes, to stay aloft long enough to arrive naked in France.

Impressive though these adventures are, the basic problem remains that there is no way of guiding a balloon.

Mail coach: AD 1784 - 1797

Benefits in both communication and travel derive from an initiative of John Palmer in 1782. As owner of a theatre in Bath, he is struck by the fact that letters to and from London often take three days on the journey - because the royal mail employs for the purpose individual postboys on decrepit horses.

Palmer proposes to the government a more ambitious scheme, by which the mail is to be carried in special coaches with good horses, armed guards, and no outside passengers. There is strong opposition from the post office, but the young William Pitt gives Palmer his personal support. As chancellor of the exchequer, he is attracted by the idea of higher postal charges for a better service.

The first mail coach runs from Bristol to London in 1784. It is so successful that by the autumn of the following year Palmer has launched services to sixteen other towns including Liverpool, Manchester, Leeds, Norwich, Dover, Portsmouth, Hereford, Swansea and Holyhead. Edinburgh is added in 1786. By 1797 there are forty-two routes in operation.

The departure of the mail coaches becomes a famous event every evening in London, for they all leave together at 8 p.m. Average speeds are now up to nearly 10 m.p.h. Edinburgh is reached in 43 hours, meaning that an answer can be received in London within four days.

19th century

The roads of Telford and McAdam: AD 1803-1815

Improvement in the speed of coaches, seen in Britain with the introduction of the Mail coach in 1784, is accompanied by similar advances in road technology. Travel in horse-drawn vehicles becomes increasingly sophisticated during a period of about fifty years, until the success of the railways results once again in roads being neglected. The early decades of the 19th century are the great days of coaching, commemorated in many paintings and prints.

Clear evidence of this new priority is the government's appointment of Thomas Telford in 1803 to undertake extensive public works in his native Scotland.

Telford constructs more than 900 miles of road in Scotland, together with 120 bridges, before transferring his attention to the important route along the north coast of Wales (leading to Anglesey and the shipping lanes to Ireland). With justification Robert Southey describes Telford as the Colossus of Roads.

Meanwhile another Scot, John McAdam, has been making great improvements in the surface quality of the new roads. He devises a system, first put into practice in the Bristol region in 1815, for improving the durability of a carriage way.

A McAdam road is well drained and is raised slightly above ground level. McAdam achieves this by laying three successive layers of graded stones, with the largest ones at the bottom. Each layer is compacted by a very simple method. The road is opened to traffic for several weeks, until the metal-rimmed wheels of carriages and carts have compressed and levelled the stones sufficiently for the next layer, of a finer grade, to be added.

Roads made by this method come to be known all over the world as macadamized. When tar is added to bind the top layer, later in the 19th century, the result is the tar macadam road - and eventually the trade name 'tarmac'.

Sections are as yet missing at this point.

The National Road: AD 1811-1852

The settlement of the Ohio valley, and the admission of Ohio to the Union in 1803, prompts the construction of the USA's first great federal road project. In 1802 the government undertakes to link the Ohio valley with the Atlantic. Construction begins in 1811 at Cumberland in Maryland, which is already reached by a state road from Baltimore.

The new highway, known variously as the National Road or the Cumberland Road, is completed by 1818 as far as Wheeling on the Ohio river. It reaches Colombus, Ohio, in 1833 and stretches as far west as the Mississippi by 1852. The route survives still, as the trunk road US40.

Built with a compacted stone surface, to the new standards pioneered in Britain by Mcadam, the National Road has an immediate effect on the economy of the frontier regions.

When the road reaches Wheeling, transportation times betweens the Ohio river and the eastern seaboard are halved. Grain, hemp and wool from the west now make their way easily to the rich eastern states where they find a ready market.

This History is as yet incomplete.
Arrow Arrow
Page 1 of 4
Arrow Arrow