IN MARCH, 1825 a magnificent al fresco dinner was

given for 200 guests in London--a strange place to celebrate outdoors at that time of year. It marked the commencement of work on a tunnel under the Thames to relieve the traffic jams on London bridges. There had been manmade tunnels ever since Adam, but this was the first to be built through a soft subsoil. The machine that made it possible was the invention of Marc Brunel, a French emigr,e inspired by the dread shipworm, whose shielded head with serrated edges and ability to line his tunnel with a hard secretion as he went provided the model for a technology that was to open up the underworld.

But the celebration was premature. Instead of three years, Brunel's tunnel took 18, cost a fortune and several lives, though it spared his brilliant son Isambard, who survived to design the 19th century's greatest railways, bridges, and steamships. During its heyday as a pedestrian crossing, the tunnel, with its arched corridors and gloomy gaslight, was a combined fair, market, and flop house, familiarly called "Hades Hotel." It is now an unremarked part of the Underground.

Seized by tunnel mania, visionaries imagined London's poor being sped through darkness to enjoy Sunday sunshine in the country. Instead, wherever cheap transport went, the city followed, obliterating fields and villages. During the 1860s a network of shallow tunnels was constructed for underground railroads. Inadequately ventilated, they choked riders on the killing coke fumes for which the authorities brazenly claimed health-giving qualities. When electrification arrived in the 1880s the deep tunnels in which Londoners sheltered from bombs during World War II became possible (Bobrick's well-illustrated book has no Henry Moore drawing of this 20th-century Hades Hotel), but as early as 1875 a subway tunnel to France, for horsedrawn traffic, was actually started. The "Chunnel" remains a project still.

The London Underground developed over decades by a very English system of trial and error. The French waited until the fin de siMecle and created theirs by fiat. But before Paris opted for a M,etro she almost got an el instead, featuring a monorail to run straight across the Place de l'Op,era. In the end she went underground, where her subsoil was already a ghost city of sewers, bone-strewn burial tunnels, and galleries for mushroom culture. The first line, each station marked by its Art Nouveau ,edicule (only seven remain), opened in 1900 after two years work by oddly mixed gangs, comprising "several ruined businessmen, a group of acrobats, a dentist and a marquis." (The crew that built New York's IRT included two poets, E. A. Robinson and John Masefield.)

The engineers who proposed designs for a New York subway system as early as the 1850s were, like Brunel, curious, heroic figures, bursting with Victorian energies and proliferating talents. Alfred Beach, first editor of Scientific American, secretly built a 312-foot pneumatic tube, carting away earth at night, in hopes of demonstrating, by a fait accompli, that tunneling under the streets wouldn't make the buildings fall down. He succeeded in this; better yet, his subway car, smoothly propelled by a mammoth fan, was capable of 60 mph. Another brilliant engineer named Robinson proposed a luxurious underground railway to run by synchronized electric clocks (this was the 1860s) and to carry freight after midnight. But subway travel remained a dream, while overcrowded els were built instead, darkening the clamorous streets.

At the century's end, New York at last got its subway. The groundbreaking ceremonies suggest an age of innocence: Sousa's band played, cannons fired 21-gun salutes, and fireworks lit the sky. The jubilation was not shared by the engineer, William Parsons, another extraordinary man, who while he labored at his plans was convinced that transport could not keep up with urban growth, and worse that cities and civilization itself were doomed. The completed subway was inaugurated by a riotous mob of 70,000 who rode up and down town, fighting, kicking, and pummeling one another.

The air below, in spite of electric power, remained foul, but the poppy-red roofs of the cars and the kiosks at each entrance, mimicking Turkish summer pavilions (not even one is left), gave the ride underground a modest esthetic value. Even advertising, for a high-minded moment, was forbidden. At a nickel a ride, the subway ran at a $6 million annual profit.

In recent years subways--with the horrible exception of New York's--have made underground travel ever more convenient and agreeable. Nothing built since the 1930s can rival the Moscow metro for splendor and efficiency, though its human cost was wicked. Under the charge of Nikita Khrushchev, 80,000 "volunteers" built it "the bolshevik way"--no one knows how many were crushed, drowned, or died of the bends. The elegant subways of Mexico, Stockholm, Washington, Rome, and Tokyo provide excellent service at no such intolerable price, though the overcrowding in the Tokyo underground has put Japanese ingenuity to the test: the exertion of getting into a packed car is "a good pre-work warmup" and "rush-hour coats" are sold with "a slippery surface for slithering through crowds."

Labyrinths of Iron is skillful in its description of engineering and financial problems and lively with anecdote, though without a coherent thesis. Bobrick, who writes well, is a poet (though one who misquotes "The Deserted Village") and he uses the underworld as an ominous metaphor. Virgil's Hades was recreated in the 18th century not by nature but man, who built underground cities for coal mining while the green fields above became a burning wasteland where the only chirp heard was not that of birds but windlasses. The agent of this transformation was in a sense the subway. "The first railway had in fact been a sort of subway, serving the underground cities of iron and coal. It emerged from the mine, carrying its message across the land, then plunged back into the earth, in time taking much of the rest of the world along." And there, in the Underworld, those who place their faith in nuclear deterrence imagine that life can go on.

Even the M,etros' dragonfly ,edicules can hardly rival the soaring splendors of the stations built during the great age of railway travel, which are celebrated and thoughtfully criticized in All Stations, the catalog of a fascinating exhibition that lately toured Europe.

When they were new, early in the 19th century, railway stations were seen as symbolic gateways to distant places, to the future itself, paradoxically constructed both to welcome that future and disguise it from the anxious traveler. Behind the architect's noble essay in the style of a Roman bath or a gothic cathedral lay hidden the engineer's great iron-and-glass train shed. A 19th-century photograph (not in the book) of a runaway engine that has burst through the renaissance facade of the Gare de l'Ouest represents this paradox with a surreal concision.

Stations built later in our century have come to renounce the rich emotional content of their forerunners for a cold, inhuman neutrality confirmed rather than alleviated by inescapable canned music. Nothing demonstrates this contrast better than the destruction of London's Euston Station, with its free-standing Doric arch and noble waiting room for a replacement resembling a garage.

This handsome book is replete with the fantasies in iron and stone of a richer past--the spectacular green- and-gold buffet of a Moscow station that dwarfs the diners; the great vaulted spaces of Pennsylvania Station, pitilessly wrecked and replaced by a cheap tower block that hides the trains in its sinister basement; a project for a central station in Paris resembling (to paraphrase Sydney Smith) a Grand Palais that has farrowed; the huge fortress station of St. Louis, now useless in a land that has scuttled the railway.

The exhibition does not ignore the station's central part in the tragedies of modern history, and a terrible image lingers of three tracks leading to the entrance to Auschwitz on a dark winter day. Thin snow etches the roof tiles, the ties, a heap of discarded jugs and basins. The tracks join to pass through the gates of hell.y