29 May 2014

Strand / Aldwych Underground Station

Aldwych underground station was closed to passengers in 1994, but it had never been used to its intended extent. At the end of a spur from Holborn, off the Piccadilly line, the station was built upon the site of the Royal Strand Theatre, and opened on 30 November 1907.

The Piccadilly line was one of three completed in 1906/7 by the Underground Electric Railways Company, a creation of American entrepreneur Charles Tyson Yerkes, who had built rail and tram lines in Chicago. The station was opened as Strand, but the name was changed to Aldwych on 1 May 1915 to avoid confusion with Charing Cross Strand, which in that year was renamed Strand - the latter reverted to Charing Cross in 1979.

The architect was Leslie Green, all of whose underground stations boast facades of deep red glazed brick and terracotta, from the Leeds Fireclay Company. The entrances, one on the Strand (top), and another on Surrey Street (second photo), initially bore the legend Piccadilly Tube, but this was changed to Piccadilly R[ail]l[wa]y.

All of Green's stations are constructed using a load-bearing steel frame, a Chicagoan innovation that provides strength enough for lift-winding equipment. Aldwych was a deep station, the platforms over 92 feet below street level, and three lift shafts were sunk, anticipating extensions never realised (third photo).

Being so close to both Temple and Embankment stations, Aldwych was never busy, and only one of the shafts was ever fitted out, with a pair of inter-linked lifts (fourth photo), operated by a dedicated liftman.

Anticipating low usage, and for reasons of economy, only the intended exit set of stairs and passages was completed, experimentally painted at ground level with fluorescent paint subsequent to the King's Cross fire (fifth photo). The intended entrance set was never used and was left unfinished (above).

There were two tunnels to the station, which boasted two platforms, but the eastern tunnel (above) was not used after 1914, with just a two-car shuttle run to and from Holborn in the western tunnel.

The station was shut on Sundays from April 1917, and in 1922 the booking office was closed, with tickets instead sold in the lifts. Access these days is solely via 192 steps. At the bottom of those to the eastern platform can be seen various tiling schemes (below), as the station was used as a test bed.

The western platform, complete with tube train, is used for filming purposes - the posters here are reproductions - and as a training facility by the emergency services: the line to Holborn is still usable.

The original station name can be seen on the disused eastern platform (remainder of photos), used during WWI for the safe storage of over 300 paintings from the National Gallery. The track is the original, on wooden sleepers, built to the pattern used before the introduction of the suicide pit. The posters are from the 1970s, testament to the quality of the adhesives tested here.

The eastern platform and tunnel were used during WWII to store items from the V&A and the British Museum, including the Elgin Marbles, and were full by March 1940. It wasn't until September that year that the service to Aldwych was suspended and the western platform and tunnel provided as an air raid shelter, opened in October.

The Aldwych shuttle service started up again in July 1946, but was not much used. From June 1958 the service was reduced to one at rush hours only. The death knell came in 1994 when the lifts required replacement. As by that point only 450 people per day were using the station, Aldwych closed on 30 September 1994.

Clifton Suspension Bridge - 150 Years

Although one of Brunel's masterpieces, the Clifton Suspension Bridge was neither completed during his lifetime, nor to his design. Commenced in 1831, the structure at Clifton was of the very first generation of wrought iron chain suspension bridges, absolutely at the cutting edge of the engineering of the time. Built at Clifton to take advantage of the relatively narrow width of the Avon Gorge at that point, the deck is 245 feet above high water.

A first design competition was conducted in 1829, three years after Thomas Telford had built his suspension bridge over the Menai Straits. The competition committee asked for Telford's expert opinion on the entries, which included four by Brunel. Telford declared all the designs flawed, and was asked by the committee to submit his own scheme. His short-span suspension bridge was responded to with a new, cheaper, design from Brunel.

Accordingly, a second competition was held in 1830. Smith and Hawkes' scheme was selected as the winner, and Brunel's abutment-based design placed second. Brunel, aged just 24, managed to reverse these placings after private meetings with the committee's expert advisers, and work commenced in June 1831. Four months later a shortage of funds, and riots in Bristol, brought progress to a halt. Work did not re-commence until August 1836, starting with the abutment on the Leigh Woods side. That on the Clifton side, left of picture at top, was commenced in 1839.

The abutments, of grey Pennant rubble stone faced with dressed Old Red Sandstone, are of different heights, to account for the taller and steeper cliff on the Clifton side. They were thought solid until found, in 2002, to be formed of a series of massive chambers. By 1840 the towers, 702 feet apart, 86 feet high, and of about 4,000 tons each, were complete. Next came the anchorages, inclined tunnels cut 60 feet into the cliffs, into the depths of which are carried the ends of the chains. These are locked behind cast iron anchor plates, of 30 square feet, bolted to the rock, and reinforced by 10 feet of Blue Staffordshire brickwork. These were completed in 1842, in which year the towers were topped with cranes to enable construction of the chains.

The chain links, the shortest 24 feet long, had largely been delivered when funds again dwindled. By 1848 the Copperhouse Foundry, Hayle, Cornwall, that had made the links, issued proceedings for payment of its invoices. The debt was repaid only through sale of the chain links, which ended up on the Royal Albert Bridge at Saltash, also by Brunel. The Clifton project came to a second halt in 1853.

Brunel died in 1859. The following year John Hawkshaw designed the Charing Cross railway bridge. This replaced Hungerford Suspension Bridge, another Brunel construction, and Hawkshaw and fellow engineer William Barlow proposed that the Hungerford ironwork be used at Clifton, the links being of the same design as those sold for the bridge at Saltash.

Hawkshaw and Barlow made some design changes - longitudinal deck girders instead of timber trussing, a third chain, and new anchorages - and work re-commenced in November 1862. The Hungerford saddles were installed atop the towers in 1863, and eight wrought iron cables were strung across the void, to provide temporary falsework. The chains, of 4,200 links, were in place by May 1864.

The deck is attached to the chains by way of iron rods, which are in turn bolted to the bottom, middle and top chain, to ease replacement. Once the longitudinal girders were craned into place, the cross bracing was undertaken. The deck itself was formed of five inch thick Baltic pine, laid in two layers, at right angles to each other. The bridge finally opened on 8 December 1864.

The roadway was first asphalted in 1897, and the anchorages strengthened in 1925 (Leigh Woods) and 1939 (Clifton), but, in the main, the structure is just as it was 150 years ago. No steel cables have been added, as has proven necessary with some other early suspension bridges. Brunel didn't see the completed bridge, but he would have known that it was, and is, an engineering marvel.

Clifton Observatory

A splendid view of the Clifton Suspension Bridge can be had from a balcony cantilevered out from the mouth of Ghyston's, or St Vincent's, Cave, 90 feet below the top, and 250 feet above the foot, of St Vincent's Rocks.

The tunnel to this, excavated by the artist William West, is accessed from the nearby Grade II listed Observatory. This started life in 1766 as a corn mill, was later used to grind snuff, and was abandoned in 1777 when a strong gale over-drove the sails and set light to the mechanism.

West rented the mill from 1828, used it as his studio, and installed a camera obscura. He also determined to link the Observatory to Ghyston's Cave, previously accessible only via the cliff face. The cave has at times served as a chapel, is first mentioned as such in the early fourth century.

The tunnel, through limestone, is 2,000 feet long, took two years to cut, and first opened in 1837. Stone and brick steps make an initial descent, which is continued more gradually by way of concrete steps. A metal stairway drops into the cave, from which there are steps up to the suspended balcony.

20 May 2014

Good Head, Croydon

At the heart of Park Hill, Croydon, stands a water tower, built in 1867 above a pre-existing reservoir of 1851. The latter was constructed underground. Circular brick walls 30 feet high were capped with a domed roof. Of 75 feet diameter, the reservoir held a maximum of 950,000 gallons. Unfortunately, this facility proved incapable of serving the luxury properties built upon the higher ground on the then outskirts of Croydon, and the tower was constructed to provide suitable water pressure.

30 feet in diameter and 100 feet high to the top of the turret (excluding the 25 feet below ground), this was designed by Baldwin Latham, Borough Engineer, in a pseudo-Norman style. It incorporated a cylindrical wrought iron tank of 40,000 gallons capacity, borne on cast iron girders and intervening timber joists. Additional support of the tank came in the form of the central cast iron inlet, outlet and overflow pipes.

In the basement of the tower was an additional tank of 94,000 gallons capacity, on a level with and connected to the earlier reservoir. This lower tank had an internal diameter of 27 feet, with a brick and stone pier at its centre, supporting the pipes to the upper tank. The water stood 27 feet deep. The whole structure stands upon four feet of concrete, the walls 5 feet 5 inches thick at the bottom of the lower tank, of 3 feet 2 inches at ground level, and 14 inches thick at the tower's top.

In the late nineteenth century the tower could be climbed, by stairs, to access a viewing platform and, indeed, during WWI was used as a lookout for Zeppelins. Its water-providing abilities ultimately proved inadequate, and the site was abandoned in 1923 subsequent to construction of a new reservoir in the Addington Hills, although the old reservoir provided a source of water for fire-fighting during WWII. The tower was Grade II listed in 1970, but the tanks and internals are all gone, and the building remains abandoned, although thankfully secure.

16 May 2014

Taywil Hero Mangle Press

Taywil Hero Machine mangle disassembled and all elements wire-wheeled. Cast iron frame drilled for bolting-in of print bed support, and painted with three coats of red and two coats of black metal paint. Components painted with two coats of black paint, bearings stripped and regreased, and springs replaced. Components test assembled.

Wooden rollers treated for woodworm, and turned down on a lathe to a reduced diameter. Rollers sheathed with stainless steel tubes of ¼" wall thickness - the most expensive items of the project. Drive and transfer wheels re-fitted and painted as per frame and components, and handle coated with two applications of sealing woodstain.

Print bed support fabricated from 2" wide steel bar, drilled to enable bolting to frame and to take stretchers, and painted as per components. Stretchers made from M10 threaded rod, bolted through steel bar supports, and positioned such that rod tops are just below mid-line between rollers.

Rollers installed and transfer wheels cover fitted. Strips of wood fitted underneath original wooden top board, with a small gap between - to hold printing paper out of the way until nipped by rollers - and treated as per handle. Print bed can be sealed medium density fibreboard (MDF) or sheet steel. Mangle now a printing press, for linocuts, plate engravings and etchings, and woodblocks (up to tooth depth of transfer wheels), to a maximum of 20 inches wide.

Taywil was a brand of Taylor and Wilson, of Clayton, near Accrington, Lancashire. Founded in 1866, they made washing and mangling machines, and step-ladders. Later Taywil's trade listings included gas-heated boilers and garden seats. Their Royal Mill, in Atlas Street, closed in 1962/3, the front demolished to make way for the M65 motorway.

12 May 2014

Philips Pancake Loudspeaker

Shaped by the industrial designer Louis Kalff, the Philips 'pancake' or 'shaving-plate' loudspeaker was available in three diameters. The Model 2003, of 16 inches, was introduced in 1927, price £6 10s 0d. The Model 2015, of 14 inches, price £5 5s 0d, was introduced in 1928, when the larger model became known as the Senior and the smaller as the Junior.

When Philips introduced, in 1929, the Model 2007, of 18 inches, price £7 10s 0d, it was unaccountably marketed as the Peter Pan. This largest model featured a three-position rotary switch in the connecting lead, allowing for alteration in impedance and, hence, tone. The horseshoe magnet, balanced armature and parchment cone of the loudspeaker sit behind the inner Bakelite dish, the outer parabolic bowl acting as a sound reflector.

Whilst the Model 2015 could be had only in maroon Bakelite (what Philips for trademark reasons called Philite) the two larger models could be had in brown, buff, maroon, and marbled colours. This Model 2003 has glorious gold patterning, resulting from the inclusion in the Bakelite mix of brass powder.

Although without a cabinet, the Model 2003 weighs a hefty seven pounds, partly due to the cast iron foot upon which it stands. The heaviest version though was Philips of Sydney's 1929 promotional Big Bill, a Ford Model A truck made to look like it carried a giant pancake, but actually packing a 500w public address system. Production of pancake loudspeakers continued at Eindhoven until 1930.

08 May 2014

Edgbaston Bunker

Below the garden of what was originally an Edwardian family residence in sedate Meadow Road, Edgbaston, Birmingham, lies a Cold War bunker. Constructed in 1954 to be used by up to 80 civil defence bureaucrats in the event of nuclear war, the extensive facility is a single-storey structure in concrete, with steps down from one entrance (top) and up to two fire exits (below).

The bunker could produce its own power, using diesel engines and generating sets, and had its own store of water. Never used for its intended purpose, in 1956 the space provided temporary shelter to refugees who had fled the Hungarian Uprising.

The mansion and surrounding land, including the bunker, was sold by Sandwell Metropolitan Council, for the West Midlands Fire and Civil Defence Authority, in 1990. The council made it a rather insane condition of the sale that, if nuclear war had not broken out by 2003, the bunker was to be demolished. It's still there.

At points during the 1990s the bunker was reportedly used for raves. It was at some juncture converted by the owners into a social club, complete with bar (above), pool table, band practice room, and skittles alley, originally the main corridor (below).

The naivety of those 'preparing' for nuclear war is illustrated by the fact that the bunker lies downhill from a large reservoir, damage to which would have flooded the secure site. Ironically, it was fire, in the form of arson, that ultimately did for something that would supposedly survive a nuclear attack.