Part 2 of Wonders of World Engineering was published on Tuesday 9th March 1937, price 7d.
Part 2 was a standard issue of 32 pages. The issue included a superb folding colour plate showing a cutaway drawing of the Mersey Tunnel which accompanied an article with the same title. There was also a central photogravure supplement illustrating the article on Building the Boulder Dam. All these are illustrated below.
Our cover this week shows two of the intake towers of the Boulder Dam.
WELDERS AT WORK joining two of the pipes. The ends of each pipe were expanded to accommodate a sleeve which fitted into the adjacent ends of two contiguous pipes. Ten or eleven 40-feet lengths of pipe were welded together above the ground by men wearing protective goggles. These longer sections had to be joined by men working in pits dug under the trench in which the pipes had been laid.
The design and construction of the Mersey Tunnel. The world's largest underwater tunnel runs beneath the River Mersey for a distance of nearly three miles and joins Liverpool with Birkenhead. It took nine years to build and presented unusual engineering problems. The building of this tunnel is an achievement that represents the concerted energies of thousands of men over a period of years, and the result of their work is an imperishable record of successful achievement. This chapter was written by Peter Duff and is the first article in the series Below the Surface.
Click on the icon to see a short British Pathe newsreel clip of the opening of the Mersey Tunnel by HM King George V on 18 July 1934.
The construction of the pipe line from Kirkuk in Northern Iraq to the ports of Haifa and Tripoli on the Mediterranean coast, concluded from part 1.
The Main Entrance to the Mersey Tunnel
THE MAIN ENTRANCE TO THE TUNNEL at Liverpool is situated in the Old Haymarket. The subsidiary entrance is conveniently placed to serve the dock system. The length of the main tunnel is 3,751 yards, and the branch tunnels on either side of the river bring the total length of roadway to 5,064 yards. Work was started on the Mersey Tunnel on December 16, 1925, and it was officially named Queensway and opened by King George V on July 18, 1934.
The World’s Largest Underwater Tunnel
The coloured folding art plate presented with this issue.
THE WORLD’S LARGEST UNDERWATER TUNNEL runs beneath the river Mersey between Birkenhead and Liverpool. On either side of the river the tunnel has two entrances, the subsidiary tunnel having an internal diameter of 26 feet. The main tunnel, which has an internal diameter of 44 feet, has a length of 3,751 yards. The width between the kerbs is 36 feet, sufficient for four lines of traffic. The ventilation of this huge tunnel, through which 4,150 vehicles an hour can pass with intervals of 100 feet between them, was a complicated problem. Six enormous ventilating stations were built, three on either side of the rive, to house the gigantic fans.
The flow of the mighty Colorado River has been controlled by the building of one of the world's greatest barrages. The Boulder Dam gave employment to six thousand men for four and a half years. This article begins a new series, Triumphs of Irrigation, a subject that has affected the lives of thousands of people. This series opens with a chapter by D. Wilson MacArthur, dealing with the Boulder Dam, a dam which controls the mighty waters of the Colorado River in the USA. It is one of the greatest dams in the world. For four and a half years six thousand men were employed on this masterpiece of construction.
Click on the icon to watch a 35 minute film about the construction of the Boulder Dam produced by the US Department of the Interior Bureau of Reclamation
A London Loop Road
AT ITS EASTERN END the North Circular Road crosses the marshes of the Lea valley, between Hale End and Edmonton, by a viaduct of reinforced concrete. The two pylons shown at the top of this page mark the entrance to this viaduct and the illustration in the middle shows the concrete pillars and transverse members which support it. From the western end of the viaduct the road continues through Edmonton, Palmer’s Green, New Southgate, Finchley and Hendon; then it runs southwards through Neasden and Stonebridge Park. Near Stonebridge park, Middlesex, the road is crossed by an aqueduct carrying the Grand Junction Canal. The bridge over which this passes is of reinforced concrete, and it maintains the canal 25 feet above the road level. Raised footpaths are provided for pedestrians at this point. The aqueduct is about a mile north of of the point where the North Circular Road crosses Western Avenue, one of London’s newer arteries. South of Western Avenue the road continues down Hanger Hill to Ealing Common, and thence, via Gunnersbury Lane, to its junction with the Great West Road at Chiswick.
The Main Features of the Boulder Dam
THE MAIN FEATURES OF THE BOULDER DAM: (1) The Arizona spillway, over which water flows when the lake reaches its highest level. (2) A highway from Nevada to Kingman, Arizona. (3) The bed of the Colorado River below the dam. (4) Canyon wall outlet works. (5) and (7) The intake towers. (6) The highway, 45 feet wide, across the top of the dam. (8) Mixing towers where the concrete was prepared. (9) Spillways on the Nevada side. (10) Boulder Lake, created by the building of the dam.
Building the Boulder Dam:
THE TASK COMPLETED. While a huge reservoir is forming above the dam, water escapes through twelve valves, six on either side of the canyon, to maintain the steady flow of the river below the dam. This water falls into the river from a height of 180 feet, 13 feet higher than Niagara Falls. At the foot of the dam is the power house, and in the foreground are the openings of the tunnels through which water was diverted while the dam was being built.
Building the Boulder Dam - 2
THE FOUNDATIONS OF THE DAM were laid 139 feet below the normal water level of the Colorado River, shown by the positions now occupied by the bases of the intake towers (see photo below). Some 3,400,00 cubic yards of concrete were used in the building of the dam, and this enormous volume of material was mixed in two plants near the site of the dam. In the right foreground is the spillway on the Nevada side of the river. The network of specially built roads, bridges and cableways gives some idea of the size of the undertaking.
Building the Boulder Dam - 3
SECURING ANCHORAGES from which drillers swung by ropes during the early stages of the work. Hanging hundreds of feet above the river, on the precipitous walls of Black Canyon, gangs of men worked for many months through the terrific heat of summer, drilling, blasting and fixing anchorages for cableways and suspension bridges.
The manufacture of gas releases valuable by-products of coal which are put to innumerable domestic and commercial uses. Coke, tar, benzole, ammonia and naphtha are among the commodities that are extracted during the distillation of gas from coal. Gas production is one of the most important industries in the world. The chapter is by F E Dean.
Click on the icon to view a short British Pathe newsreel clip featuring various gases and a brief visit to a gasworks.
BECKTON GASWORKS, belonging to the largest gas company in the world, occupies about 280 acres of land on the north bank of the River Thames to the east of the Royal Albert Dock. The gasworks supplies about 40 per cent of the requirements of the area served by the Gas Light and Coke Company. Two piers on the 2,500-feet river frontage facilitate the reception of raw materials and the dispatch of by-products. The plant is capable of producing 120 million cubic feet of gas a day.
The Sao Paulo Railway, which climbs the Serra do Mar and rises to a height of 2,625 feet in five miles, links the great plateau of Brazil with the South Atlantic Ocean. The cliffs are scaled by one of the most spectacular cable railway systems in the world. The Sao Paulo Railway was a brilliant piece of engineering work, and this article is concluded in part 3.
TWO OF THE VIADUCTS on the Serra do Mar inclines. In the foreground is the older and in the background the newer incline. Nearly four thousand tons of steelwork were used for the sixteen viaducts over which the newer line passes. The total length of the viaducts which carry this line is 1,508 yards. The first line was finished in 1867, and the building of the second began in 1895.