Shipping, Technological Change

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Shipping, Technological Change

In comparison with the tremendous changes that occurred in shipping after 1800, the several centuries earlier witnessed relatively little change in the technology of shipping. As late as 1850 world seaborne trade was conducted largely by sail vessels, but in less than a century merchant sail craft were obsolete. Although sail served maritime commerce well for many centuries, all sail vessels-at the mercy of wind and tide-were notoriously irregular. With the expansion of world trade, shippers and shipowners could only wish for a means of running vessels according to a set schedule. Change really began during the Industrial Revolution, starting in Britain by the late-1700s and then spreading worldwide. The most important industrial product into ocean shipping was the steam engine. Steam provided a new way of propelling vessels, one that eventually ended the long supremacy of wind-powered craft. In its turn, steam was replaced by a new means of propulsion in the twentieth century.

STEAM ENGINES

As early as the seventeenth century, French engineers carried out the first experiments in steam-driven vessels, but with little long-term success. It was more than a century before practical steam engines were developed. The first steam engine specifically intended for maritime use was produced by Glasgow inventor James Watt in the 1760s, under the aegis of his firm, Boulton, Watt & Co. From 1800, when his master patents expired, other engineers and inventors eagerly built on Watt's pioneering work.

A number of steam experiments had been carried out contemporary with Watt's work. John Fitch operated steamers on the Delaware River in the 1780s. Although they were embryonic devices, one of his later craft carried passengers. Despite Fitch's success, the vessel generally considered to be the first practical steamboat was not launched until 1801. Its creator was William Symington, who, along with Patrick Miller, had already developed a small steamer used on Loch Dalswinton in 1788. Symington's Charlotte Dundas operated on the Forth and Clyde Canal. On one occasion, in 1802, the craft towed two loaded seventy-ton barges almost twenty miles in six hours. This was a good performance, but the Charlotte Dundas' s wash supposedly damaged the canal's banks, and it was not a long-term success.

Still, more developments followed. 1807 saw the appearance of Robert Fulton's Clermont, which ran on the Hudson River. In 1812 the Comet, Europe's first passenger steamer, entered service on Scotland's River Clyde. The Comet was one of the first steamers to live up to all of its builder's expectations, giving the Clyde predominance in shipbuilding and marine engineering. Although many of the first vessels were one-of-a-kind experiments, the building of steamers-especially in Britain and America-gathered momentum until 1820. In 1819 an American vessel, the Savannah, made an Atlantic crossing partially under steam, although the first to do so primarily using steam was the small Canadian-built Royal William in 1833. By the late 1830s vessels like Isambard Kingdom Brunel's Great Western were making the first regularly scheduled Atlantic passenger crossings.

Most early steamers were paddle wheelers with the paddles mounted on large wheels at the sides, or less frequently, the stern of the vessel. Although an efficient form of propulsion, good in shallow waters, the paddle wheel has its drawbacks. The wheel is vulnerable to breakage from collisions with flotsam. In high seas the roll and pitch of a steamer could also lift the wheels out of the water, lessening their effectiveness. The greatest problem was the amount of space needed to accommodate the large engines and paddle arrangements, high up in a vessel. Often located amidships, these took up prime cargo and passenger space. This was also a problem for naval vessels because they lost a portion of their gun space, not to mention the engine's vulnerability to enemy fire so far up in the superstructure. An alternative was clearly needed. The solution originated with a principle over two thousand years old. Alexandrian inventor Archimedes had devised a water screw system for irrigation, still used in Egypt today. By applying this principle to the provision of outward thrust, rather than water-lifting power, the modern bladed propeller got its start. Screw propulsion originated in the 1830s with the work of British inventor Sir Francis Pettit Smith and Swedish engineer John Ericsson. The superiority of the screw was established by the Royal Navy's famous tug-of-war between the paddle wheeler HMS Alecto and the screw-propelled HMS Rattler. Rattler towed Alecto along at two knots while she paddled the water at full steam. One of the first merchant screw vessels was the Archimedes of 1838, used in the English coasting trade with a top speed of eight knots. By the late twentieth century, further improvements, including controllable pitch propellers-allowing angled adjustment of the blades to suit operating conditions-have appeared, but the basic idea remained unchanged.

What effect did these developments have on world trade? Before 1850 the answer would have been, "not much." By 1900, though, everything had changed. In 1850 the bulk of overseas trade was still carried in sail craft, and passengers were only just beginning to appreciate the convenience of regular, scheduled service. The major drawback of early steam engines was their inefficiency, burning enormous amounts of coal on long voyages. This created expenses for shipowners not only from the cost of the coal, but also by the amount of cargo space lost to onboard coal bunkers and the need for coaling depots. These problems were not as serious for short routes; many coastal and riverine trades in Britain and America were dominated by steam long before the nineteenth century ended. On longer routes only cargoes of high value relative to size, or those where fast, on-time delivery was at a premium, were transported by steamer. Some trades, such as those from Britain to the Antipodes, remained largely sail at the turn of the twentieth century.

In 1869 Egypt's Suez Canal opened. This event was very important for steam shipping. In Britain's valuable India trade, the distance was reduced by about half compared to the Cape of Good Hope Route. At a stroke, bringing cargoes to and from such destinations by steamer became feasible, especially since sail vessels could not use the Canal. The value of Suez was further enhanced by the development of ever more efficient steam engines.

The main task for engineers was to increase the power produced by their engines while reducing coal consumption. One innovation was the surface condenser, which maximized the efficiency of marine boilers by permitting use of fresh water and eliminating corrosive brine. Along with fresh-water feeds, the surface condenser allowed raising of boiler pressures from only 5 lb per sq. in. before 1835 to 200 lb per sq. in. in 1900.

New types of reciprocating engines appeared in the 1800s, the most important being the compound engine, developed in 1853 by John Elder and Charles Randolph. The compound engine added an extra cylinder to the steam engine. This produced an effect as though the same amount of steam was being used twice, allowing the engine to perform more work. The compound engine significantly reduced coal consumption, and in 1856 Pacific Steam Navigation Company became the first major shipping line to employ compound engines. Elder took out patents for triple- and quadruple-expansion engines in 1862, adding even more cylinders and power. Further improvements were contributed by men like Alfred Holt, who built simplified versions of the engines, freeing up more vessel space for cargo.

The ultimate development of the steam engine appeared at the end of the nineteenth century-the steam turbine. Like the screw propeller, the idea for the turbine was an ancient one. Essentially, steam would be used to drive blades mounted on a rotor shaft. The high velocity of a steam jet meant that necessary blade and rotator speeds for large machines exceeded contemporary engineering capabilities. The solution was eventually provided by Irish mathematician Charles Parsons. In 1884 he mounted blades on a series of wheels, increasing in size, creating the first successful turbines. His experimental vessel Turbinia was unofficially showcased at Queen Victoria's Jubilee Naval Review in 1897. Application of the technology to merchant craft began in 1901 with the King Edward. Turbines gave steamers improved fuel consumption and better performance at high speeds, although early models were difficult to steer and not as efficient at lower speeds as reciprocating engines. These difficulties were largely overcome in later models. Eventually some turbines, like the QE II's original engines, had an output of 55,000 shaft horsepower. In 1952 one of the fastest ever Atlantic crossings was made by the turbine-powered liner United States at over thirty-five knots.

HEAVY-OIL ENGINES

About the time the turbine appeared, the first workable heavy-oil engines were developed. Engines based on the work of Rudolph Diesel are the main power plant in modern merchant vessels, although it was some time before the design took hold. In 1910 a Dutch tanker was fitted with a 450-brake horsepower engine.

The first ocean-going diesel cargo liner followed in 1911, although the diesel vessel, or motorship, has enjoyed its greatest success since the interwar period. A majority of Scandinavian and a quarter of world tonnage was diesel by 1939. The diesel engine was initially slow, expensive, and difficult to reverse. Improvements such as lightweight engines with reduction gears, have made the diesel almost unbeatable as a marine engine in terms of fuel economy.

Developments during the twentieth century, such as diesel-electric machinery, have enhanced the original concept's performance. Alongside the motorship, steam turbines are still used for some of the largest merchant vessels. There have also been experiments with nuclear-powered merchantmen and attempts to develop more efficient coal-driven vessels. Still, at the dawn of the twenty-first century, most merchant shipping-and thus most world ocean trade-is powered by the successors of Diesel's original 1892 engine.

SEE ALSO Baltic Exchange; Cargoes, Freight; Cargoes, Passenger; Containerization; Empire, British; Empire, Dutch; Empire, Portuguese; Empire, Spanish;Hanseatic League;Onassis, Aristotle;Panama Canal;Petroleum;Shipbuilding;Shipping, Aids to;Shipping, Coastal;Shipping, Inland Waterways, Europe;Shipping, Inland Waterways, North America;Shipping Lanes;Shipping, Merchant;Ships and Shipping;Ship Types;Suez Canal;Sumitomo;United Fruit Company;United Kingdom.

BIBLIOGRAPHY

Allington, Peter et. al. Conway's History of the Ship: The Advent of Steam. The Merchant Steamship Before 1900. London: Conway Maritime Press, 1993.

Bowen, John et. al. Conway's History of the Ship: The Golden Age of Shipping. The Classic Merchant Ship 1900–1960. London: Conway Maritime Press, 1994.

Bruce, J. Graham. "The contribution of Cross-Channel and Coastal Vessels to Developments in Marine Practice." Journal of Transport History 4 (1959): 65–80.

Corlett, Ewan. The Ship: The Revolution in Merchant Shipping 1950–1980. London: Her Majesty's Stationary Office, 1981.

Gardiner, Robert, ed. The Advent of Steam: The Merchant Steamship before 1900. Annapolis, MD: Naval Institute Press, 1993.

Gardiner, Robert, ed. The Golden Age of Shipping: The Classic Merchant Ship 1900–1960. Annapolis, MD: Naval Institute Press, 1994.

Henning, Graydon, and Keith Trace, Keith. "Britain and the Motorship: A Case of the Delayed Adoption of New Technology?" Journal of Economic History 35 (1975): 353–385.

Maddocks, Melvin, and the editors of Time-Life Books. et. al. The Seafarers: The Great Liners. Chicago; Alexandria, VA: Time-Life Books, 1982.

David J. Clarke

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