The First Subways

Overview

The growth of railroads in the middle of the nineteenth century coincided with improvements in tunneling techniques. Underground railway service began in London in the 1860s, as a way to help ease street traffic problems. However, the coal-fired locomotives of the day created air pollution problems in the early subway tunnels. The success of the first electric subway, which opened in London in 1890, encouraged other cities to develop systems of their own.

Background

In the early nineteenth century, city traffic was becoming unmanageable. Narrow, twisting lanes and dead-end streets built for foot traffic and mounted riders were being confronted with increasing volumes of coaches, carriages, and omnibuses. The congestion became a major civic issue in population centers such as London, Paris, New York, and Boston.

In London, the growth of the Thames dock system had led to extensive waterfront development on both sides of the river. To get from one side to the other required a ferry, or a roundabout trip via the London Bridge. Produce withered and dairy spoiled before it could be delivered to its customers. Another crossing was a necessity, and the powerful Duke of Wellington, with military defense considerations in mind, supported a tunnel rather than an additional bridge.

Yet no one had ever been able to build a tunnel in the soft silt of a riverbed. The ancients had dug passages and channels into rock, for tombs, aqueducts, and sewers. Rock was difficult to cut, but in the seventeenth century engineers learned to use gunpowder to help blast it out. And once rock tunnels were cut, they tended to stay put, because their walls were self-supporting. Trying to dig under soft earth or watery silt was a different matter.

In mining tunnels, for example, the walls were braced with wooden frames, but the miners had to dig ahead of the frames in order to progress further. It was not uncommon for soil and loose rocks to suddenly pour in, destroying both the tunnel and the miners in it. In the early 1800s, a true soft-ground tunnel had never yet been built. In 1809, after a few attempts had failed, a learned committee was formed to judge proposals for building one. A prize of 500 British pounds was offered. The judges rejected dozens of proposals and finally declared the entire idea "impracticable."

Civil engineer Marc Isambard Brunel (1769-1849) thought the committee's conclusion was ridiculous. In 1818, he patented the tunneling shield. Miners stood inside a number of what were essentially huge hollow cast-iron drill bits, which were pushed forward through the earth six inches (15 cm) at a time by hydraulic presses. As the shield crept forward, it provided the supportive structure to hold the tunnel up. Meanwhile, behind the protection of the shield, each successive six-inch section of tunnel wall was bricked over.

With Wellington's support, Brunel gained the approval of the British government for his scheme. He broke ground for the Thames Tunnel in 1825. Building the tunnel was an arduous process. Financial directors insisted on piece-work wages, paying by the amount of ground covered or number of bricks laid, rather than by the hour. This led workers to take dangerous shortcuts. A collapse in 1827 led to the project's being abandoned for a decade. Finally the tunnel was opened in 1843, and 50,000 people passed through it in the first 24 hours. Although it was only 400 yards (366 m) long, it was regarded as one of the wonders of the world.

Impact

For 23 years the Thames Tunnel served as a pedestrian passage. But its arrival in the 1840s coincided with the height of enthusiasm for the new railroads, which were expected to solve all transportation problems. Rails had been used for horse-drawn mining carts and other rough-terrain hauling for hundreds of years. The invention of the steam engine by Thomas Newcomen (1663-1729) in 1712 and later improvements by James Watt (1736-1819) led to the development of the steam locomotive, capable of pulling heavy trains over great distances. Society was transformed in the early decades of the nineteenth century, as people and goods traveled more easily between cities and the countryside.

The Thames Tunnel had pointed the way to using underground transportation to ease city congestion. Railway lines crisscrossed England, but they all stopped at the edge of London. Proposals to get them into the city failed for lack of space. Underground railways were the inevitable solution, and were championed by Sir Charles Pearson, sometimes called the father of the subway. In 1854, the newly formed Metropolitan Railway Company received the Royal Assent to build an underground line in London.

A major concern about running locomotives underground was preventing the passengers from suffocating. The tunnels of the time were very poorly ventilated, and coal-fired locomotives were a pollution problem even in the open air. The Metropolitan Railway's chief engineer, John Fowler (1817-1898), attempted to assuage these concerns by promising to build a "fireless locomotive" that would build up enough steam outside the tunnel to get through it without burning any more fuel. So there would be no smoke, and even the steam would be condensed into a cold water reservoir rather than being released in the tunnel. This promising idea turned out to be impossible to implement, and the Metropolitan retreated to a standard coal-fired locomotive with a few minor modifications.

This meant it was all the more important to have well-ventilated tunnels, and so they were made shallow, with "open cuts" to the surface at intervals to allow air exchange. Brunel's shield was not appropriate for such shallow work, and so another tunneling technique called cut and cover was used. First an open trench was dug, and the sides reinforced. Then the trench was roofed over, and the surface restored, except at the open cut sections.

Cutting a 3-mile (4.8 km) trench across the ancient city of London was like stepping into a time machine. Excavators unearthed fossilized invertebrates, Roman water pipes, and ruins left by the Celts, Saxons, Danes, and Normans. The excavators were, of course, not archaeologists, but laborers and businessmen in a hurry, so one can only speculate at the knowledge that was lost.

On January 9, 1863, the world's first subway train pulled out of the Bishop's Road Station. It was packed with dignitaries, although the Prime Minister, the elderly Lord Palmerston, declined, writing that he preferred to remain above ground as long as possible. The next day the "Underground" opened to the public, and 30,000 passengers tried it out. Within a few years, companies were vying for the right to open subway lines.

Early London subways had first, second, and third class carriages, and the cars were attractively done up in Victorian style, with plush seats, brass hardware, and polished paneling. Air quality, though, was still a problem, even with the open cuts. Additional holes drilled to the surface were not sufficient to ventilate the tunnels, and served mainly to startle pedestrians with sudden blasts of smoke. Railway officials issued claims that coal and sulfuric acid fumes were therapeutic for asthmatics and bronchitis victims. Sometimes the smoke was so thick that the trainmen could not see their signals. Eventually, it became necessary to install large, expensive exhaust fans.

It had been hoped that the shallow tunnels would help with ventilation, but this was not the case. While it was understandable to have assumed that digging a shallow tunnel would be less expensive than digging a deep one, that hadn't worked out either. Shallow tunnels interfered with streams, water and sewer lines, and gas mains, and incurred the cost of buying all the property through which the trench would run. A deeper tunnel would avoid all these concerns. But it would be impossible to run steam locomotives in them.

Fortunately, refinements of Brunel's deep tunnel-digging methods coincided with the development of electric railroads. On November 4, 1890, the Prince of Wales, later to be King Edward VII, presided over the opening of the City and South London, the city's first "tube." The tubes had only one passenger class, and were pollution-free. Their success sparked further subway development in London and elsewhere. On the European continent, the first subway line opened in Budapest in 1896. The first subway in the United States, a one-and-a-half mile (2.4 km) line in Boston, opened in 1897. Work on the Paris Metro began in 1898, and it opened in 1900.

Subway development in New York got a slow start due to the machinations of the famously corrupt politician William Marcy "Boss" Tweed, who was safeguarding the interests of the omnibus and streetcar lines that paid for his patronage. There was also a great deal of sensational publicity in New York about the ventilation problems in the early London underground. A prototype pneumatic subway had a brief run in the 1870s, and a number of elevated railroad lines were built. The first underground line of the Interborough Rapid Transit Company, or IRT, opened in 1904.

SHERRI CHASIN CALVO