The ventilation shaft at City Hall Park, 1912
The ventilation shaft at City Hall Park, 1912
On the eighth of February 1912, a small group of officials arrived at City Hall Park on Manhattan's Broadway street. The men gathered at one grassy corner of the park grounds, where a long-neglected iron grating protected the entrance to a seemingly unremarkable ventilation shaft. The heavy, rust-encrusted grille was pried from its resting place, and with lanterns in hand the men descended one by one into the cavity.

About twenty feet below the pavement the group emerged into an eight-foot-wide brickwork tube, the end of which was beyond the immediate reach of the lights. The sturdily-constructed tunnel was a relic from the years following the American Civil War, and it had remained virtually forgotten beneath the streets of New York since its main entrance was sealed sometime around 1880. As the men explored, they found the tunnel in remarkably good condition in spite of its age. When they reached the end of the tube, the men happened upon the wrecked remains of a unique mechanism for transport: a pair of carriages from America's first subway, the experimental and ill-fated Pneumatic Transit System.

In the early 1800s, the city of Manhattan was infested with an overabundance of humans. When the Erie Canal opened in 1825 to link the Great Lakes with the Atlantic Ocean, New York's populace quadrupled within a span of a few decades. The metropolis was served by hundreds of horse-drawn public transportation vehicles such as street trolleys and omnibus carts, nevertheless its avenues and boulevards were engorged with carriages and pedestrians. Primitive steam-powered locomotives were put to use in certain areas, but the massive and ungainly contraptions were not yet widely adopted.

Many enterprising individuals concocted mass-transit ideas to address the traffic woes. Due to the scarcity of horizontal space, most inventions involved elevated platforms or underground tunnels. Among the proponents of subterranean transportation was one Alfred Ely Beach, the well-known inventor of a typewriter for the blind, the founder of a school for freed slaves, and the editor of a new publication known as Scientific American.

Traffic on Broadway, 1860
Traffic on Broadway, 1860
In 1849 he wrote an article in his magazine proposing a network of underground tunnels for horse-drawn trolleys, but that fancy passed once he discovered the great strides being made in England in the field of pneumatics.

Although the basic principle of pneumatic tubes was first explored in ancient times, it was not until the turn of the 19th century that practical applications began to appear. It was around that time that the Scottish inventor William Murdoch demonstrated his pneumatic apparatus, a device which used compressed air to whisk notes through a length of pipe to a distant recipient. Among the first to appreciate the potential of such systems was a London tinkerer named George Medhurst, who described some practical large-scale applications in his 1812 pamphlet concisely entitled, "Calculations and Remarks, Tending to Prove the Practicability, Effects and Advantages of a Plan for the Rapid Conveyance of Goods and Passengers Upon an Iron Road Through a Tube of 30 Feet in Area, by the Power and Velocity of Air." Therein, he described a hypothetical pneumatic vehicle:

"...an hollow tube or archway must be constructed the whole distance, or iron, brick, timber, or any other material that will confine the air, and of such dimensions as to admit a four-wheeled carriage to run through it ... The tube must be made air tight, and of the same form and dimensions throughout, having a pair of cast iron wheel-tracks securely laid all along the bottom ... and the carriage must be nearly the size and form of the tube, so as to prevent any considerable quantity of Air from passing by it.

"If the Air is forced into the mouth of the tube behind the carriage, by an engine of sufficient power, it will be driven forward by the pressure of Air against it."

Medhurst went on to describe how a large, stationary steam powerplant could produce enough pressure to propel a carriage to an average swiftness of 50 miles per hour, with a fuel efficiency of 4.2 miles per coal-bushel. At a time when the most common form of propulsion was feet-- either human or horse-- it was exciting to consider the prospect of a feasible high-speed transportation system using combinations of existing technology.

Medhurst was aware that travelers might be averse to spending long journeys sealed within dark tunnels, so he also described a claustrophobia-friendly alternative which later came to be known as the atmospheric railway. He theorized that a twelve-inch-wide iron pipe with a sealable slot along its length could be laid parallel to ordinary surface tracks, and that trains could be connected to a pneumatic piston inside the tube using an arm protruding from the slot.

A section of atmospheric railway at the Didcot Railway Centre
A section of atmospheric railway at the Didcot Railway Centre
Several such atmospheric railways were constructed in Europe during the 1840s, most notably by the innovative British engineer Isambard Kingdom Brunel. One of these peculiar trains achieved an unheard-of 70 miles per hour during trial runs, however due to chronic problems with the leather slot-seals, the technology was quickly abandoned in favor of steam locomotives.

In the meantime, smaller pneumatic tubes proved their usefulness in shuttling telegraph transcriptions betwixt London's central telegraph offices and the Stock Exchange. The newly-formed London Pneumatic Dispatch Company also began installing iron pipes in the earth for the transportation of postal freight. These pressure tubes carried coffin-sized carts between the post offices of London at speeds up to a mile a minute. Eventually a group of investors arranged for a pneumatic-powered passenger-carriage to be installed as a demonstration at the Crystal Palace Exhibition of 1864 at Sydenham, south London. This working prototype aroused much public interest, but its promoters lollygagged too long, and failed to bring the technology to fruition.

Upon learning of the strides being made by the London boffins, Alfred Beach became one of pneumatics' most enthusiastic stateside advocates. To increase public awareness of pneumatic technology, he financed the construction of a 100-foot-long wooden tube to cross the ceiling of the American Institute Fair in 1867. The steam-powered fan installed at the end of this tunnel created enough vacuum pressure to suck carriagefuls of attendees through the tube's length in mere seconds. It then reversed thrust, gently blowing the delighted passengers back to the portal from whence they entered. In his 1868 treatise on the subject entitled "The Pneumatic Dispatch, with Illustrations," Alfred Beach expounded the advantages of pneumatic locomotion:

"A tube, a car, a revolving fan! Little more is required. The ponderous locomotive, with its various appurtenances, is dispensed with, and the light aerial fluid that we breathe is the substituted motor [...] Hence, the roadway and cars may be very light. The whole pneumatic way being under cover, the road-bed is preserved from damage by the elements, and the transit of the cars is not impeded by snow, ice, floods, or falling rocks. [...] The tube forms the bridge over small streams, dives under broad waters, and rests securely upon marshes. No screeching whistles or jangling bells disturb the community, no turnpikes require to be guarded;

Alfred Beach's demonstration pneumatic carriage at the American Institute Exhibition of 1867
Alfred Beach's demonstration pneumatic carriage at the American Institute Exhibition of 1867
there is no running down of the helpless, no mangling of passengers, no burnings from sparks; no fearful dangers of any kind attend the use of the Pneumatic Dispatch. [...] No dust or cinders are encountered by the passenger, and he reaches his journey's end without injury to his apparel from these causes, and without having the complexion smutted with smoke."

Like most designers of rapid-transit contraptions, Beach hoped to establish a route along Broadway, as it was Manhattan's main thoroughfare. For over twenty years, however, a long succession of such plans had been undone at the hands of Alexander T. Stewart, the richest merchant in the United States. His grandiose Marble Palace was located on the intersection of Broadway and Chambers Street, and he was unwilling to allow any unsightly construction to inconvenience his ultra-wealthy patrons. He and his fellow landowners also worried that any large tunnels would undermine the street's structures. To sidestep this hindrance, Beach's newly-established Beach Pneumatic Transit Company sought a franchise to install a pair of smaller postal tubes below Broadway, thereby avoiding the ire of the street's mighty merchants. Upon approval of the bill, the company successfully amended it to allow the excavation of a single large tunnel wherein the smaller tubes could reside.

In late 1868, the Beach Pneumatic Transit Company acquired a five-year lease on the basement of Devlin’s clothing store on Broadway, and began their conspicuous construction. The details of the endeavor were kept quite secret, but the scale of the operation was evident from the large equipment outside of the building and the cavalcade of horsecarts hauling away mounds of dirt each night. Twenty feet beneath Broadway, a unique machine designed by Alfred Beach himself slowly gnawed a nine-foot-wide passage into the Earth. The business end of the disk-shaped tunneling shield was arrayed with sharp horizontal shelves which masticated the earth until it fell into the tunnel through a number of openings. Using an array of eighteen hydraulic rams, workers forced the shield forward sixteen inches, used wheelbarrows to haul away the loosened earth, erected masonry around the new inches of tunnel, and then repeated the process. Entry into the construction area was strictly limited to Beach Pneumatic Transit employees and the officials from the Croton Aqueduct Department-- the agency responsible for supervising construction of the "postal tube."

The Beach Tunneling Shield
The Beach Tunneling Shield
The mayor of New York City attempted to gain access to perform an inspection of the site, but even he was refused. The public and the press expressed great curiosity regarding the tunnel-making, but Beach and Dixon were determined to forestall the discovery of their true intentions.

On the twenty-sixth of February 1870, Alfred Beach finally exposed his secret tunnel for the inspection of the public. The event was described by one silver-tongued newspaperman as a "Fashionable reception held in the bowels of the Earth." Visitors entered the basement of Devlin’s clothing store by way of a vestibule which had special linked doors on either end; the inner door would not open until the outer door was closed, providing a rudimentary airlock for the pneumatic pressure. Therefrom they emerged into an ornate lobby encrusted with the stuff of high society, including wood trimmings; chandeliers; an ornate, goldfish-filled fountain; and a grand piano. Although electrical service was still a thing of the future, the underground lobby was brilliantly illuminated by a collection of new zircon oxygen/hydrogen gas lamps.

At the far end of the waiting area was the portal to America's first subway, installed "for the purpose of temporarily illustrating, by an actual demonstration, the feasibility of placing a railway under Broadway." The tunnel was framed in handsome brickwork, and two stately bronze effigies of Mercury stood alongside. On a placard above the tunnel hung the words, "Pneumatic / 1870 / Transit." For a fare of two bits per passenger-- all of which was donated to a charity for soldiers' orphans-- twenty guests at a time could take a ride on the pneumatic carriage. The custom-built, fifty-ton blower was situated in an adjacent chamber, separated from the waiting area by a long corridor. The Æolor blower was twenty-one feet high, sixteen feet long, and thirteen feet wide, and it contained two colossal lengthwise paddles which rotated to draw air in through the rear and thrust it out from the front. The magnificent blower was also outfitted with a special set of adjustable baffles which allowed her to switch from suck to blow without reversing rotation. By tapping a telegraph wire, the conductor signaled the boiler engineer to engage the 100 horsepower steam engine. Atmospheric pressure increased by "a few grains per inch," pressing the carriage into the tunnel as the air rushed to escape through the vent at the far end. As quoted in a company booklet, a visitor described her experience on the Pneumatic Transit:

"We took our seats in the pretty car, the gayest company of twenty that ever entered a vehicle; the conductor touched a telegraph wire on the wall of the tunnel; and before we knew it, so gentle was the start, we were in motion, moving from Warren street down Broadway. In a few moments the conductor opened the door, and called out, Murray street! with a business-like air that made us all shout with laughter. The car came to a rest in the gentlest possible style, and immediately began to move back to Warren street, where it had no sooner arrived, than in the same gentle and mysterious manner it moved back again to Murray street [...] Our atmospheric ride was most delightful, and our party left the car satisfied by actual experience that the pneumatic system of traveling is one of the greatest improvements of the day."

A sketch of the pneumatic carriage and lobby
A sketch of the pneumatic carriage and lobby
With a sufficiently powerful blower, it was theoretically possible to accelerate a pneumatic carriage up to almost 700 miles per hour, a far cry faster than the horse-drawn rattletraps of the surface-travelers. In another anecdote, a visitor described a harrowing encounter with the blower:

"After we had had our ride, it was only natural of course, that we should wish to explore the source from whence came the pneumatic pressure that had so mysteriously carried us along under Broadway. Accordingly, under the guidance of one of the polite officials of the company, provided with lanterns, we entered the air-passage, or duct, which opens into the waiting-room near the mouth of the tunnel. [...] As we went in, we felt a gentle breeze; but after we arrived at the mouth of the great blower, and while we were gazing in wonder at the motions of the gigantic blowing-wings, the engineer put on more steam and increased the speed, so that the blast instantly became a hurricane of frightful power. Hats, bonnets, shawls, handkerchiefs, and every loose thing, were snatched away from our hands and swept into the tunnel; while all of us, unable to stand against the tornado, hastily retreated from the machine to a corner of the air-box, where we were slightly sheltered. At this juncture the speed of the Æolor was reduced, the storm was over, and only a gentle summer's breeze issued from its enormous throat."

During its first two weeks of operation, the Beach Pneumatic Transit sold over 11,000 rides, and enjoyed lavish praise from the public and the press. With the help of Senator William M. Tweed, Beach began lobbying for the expansion of the Broadway line, as well as the construction of other pneumatic tubes throughout the city. Legislators were troubled by the broad authority the bill granted to Beach's organization, and consequently it did not come to pass. In 1872, after "Boss" Tweed was arrested for massive corruption and embezzlement, Alfred Beach attempted to rewrite history to capitalize on the public's scorn. He claimed that Tweed had not been a supporter of the project, rather he had undermined the pneumatic underdog in favor of the competing elevated railroads.

Cutaway diagram of the pneumatic blower
Cutaway diagram of the pneumatic blower
The public accepted this fabrication with such enthusiasm that the distorted facts still taint many modern retellings. But after three long years of grappling with the law, this manipulation of public sentiment helped Beach to gain approval for a modified bill in 1873, awarding his company with the legal franchise to bore beneath New York city's streets. The company engineers began drawing up plans and making surveys, estimating a relatively low cost of one million dollars per mile to install a double track. Mere months later, however, the air was let out of their pneumatic ambitions. Excessive speculation in post-Civil-War railroads had created an investment bubble which burst in 1873, triggering a severe economic depression in the US. In the wake of this calamity, investors in rapid-transit projects were nowhere to be found.

In the years that followed, Beach Pneumatic Transit lost their lease on the Devlin building basement, and the tunnel's entrance was sealed with a wall of brick. In September 1878, Alfred E Beach resigned as president of the company and moved on to other endeavors, having invested over $200,000 of his own money in the ill-fated project. He died in 1896. Two years later, the Devlin's building was destroyed by a spectacular fire, along with whatever was left of the ornate trappings of the abandoned lobby. When the building was rebuilt in 1900, the hastily-assembled brick wall was replaced with one of concrete, leaving the ventilation shaft in City Hall Park as the only means of ingress to the prototype pneumatic tunnel. Beach's experimental subway lay virtually forgotten beneath the busy street until the officials from the Public Service Commission paid it a visit in 1912. Their task was to organize the disassembly of the tunnel to clear the way for a new electric subway line; Beach's vision for subterranean transit below Broadway was finally becoming a reality. Aside from the rusted rails, the tube was found in excellent repair. Beach's pneumatic carriages were also found inside, and though they had somewhat disintegrated due to age and neglect, there was still evidence of their once-opulent decor and upholstery. Additionally, at the end of the tunnel, Beach's innovative tunneling shield remained, its wooden teeth still sunk into the earth.

Beach's original proposal for a network of pneumatic postal tubes also became a reality after he disembarked from the realm of the living. Around the turn of the century, New York City began installing hundreds of miles of medium-sized pneumatic tunnels to ferry freight between post offices, and some of these lines remained in operation until 1953. Ultimately, however, trucks proved more efficient at information-moving than the series of tubes. Many miles of these decommissioned iron transportation tunnels still linger beneath the streets of New York.

Today, the City Hall Station of the New York Subway encompasses the entire area once occupied by the Pneumatic Subway. During the new station's excavation, the Beach Tunneling Shield and one of the passenger carriages were disassembled and removed with the intent to preserve them; but neither can be accounted for after 1918. Also, according to newspaper reports from 1932, the New York Historical Society commissioned a plaque honoring Alfred E Beach to be placed in the City Hall station, however there is no evidence of such a memorial there today. Essentially there are no physical remains of Beach's experimental and ambitious subway project; it exists only in the fickle aether of history.

The notion of pneumatic transit was revisited in the 1960s by Lockheed and MIT, with the assistance of the United States Department of Commerce. Together the organizations conducted feasibility studies on a system of magnetically levitated tube-trains powered by ambient atmospheric pressure and "gravitational pendulum assist." Such pneumatic vactrain technology was demonstrated to be a superior mode of transportation in many ways, not the least of which was speed-- the study indicated a typical line could achieve an average velocity of 390 miles per hour. The system was never built due to the enormous expense of such an undertaking, although research into related technologies continues even today. Perhaps in the distant future mankind will traverse the countryside in a pnetwork of pneumatic tubes; and if that fine day ever comes, Mr Alfred E Beach and his extraordinary 138-year-old experiment will finally be vindicated.

Topic suggested by Steve Keppel-Jones.

Written by Alan Bellows, posted on 29 February 2008. Alan is the founder/designer/head writer/managing editor of Damn Interesting.
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