The First Three Month's Work.
This article appeared in The Sydney Mail on October 31, 1923, one of a series of about 29 by Kathleen Butler. The original poor quality newspaper printed images have been substituted with better images where they can be found, or supplemented with similar images where the identical photo cannot be located.
Saturday July 28th. was a memorable day in the history of the Sydney Harbour Bridge, when the Hon. T. T. Ball M.L.A., Minister for Public Works and Railways, turned the first sod of the northern railway approach to the bridge. The ceremony, which took place on the site of North Sydney station at Blue-street, was attended by thousands of residents from both sides of the harbour, who were anxious to see the beginning made with this gigantic undertaking. At the function the chief engineer, Mr. J. J. C. Bradfield, announced that he was prepared to begin work on the following Monday, and on July 30th, with his field staff, consisting of Mr. K. Fraser resident engineer, Mr. W. Roper, assistant engineer, and Mr W. Shepherd, foreman, established his office at Bolwarra Flats, at the corner of Walker and Blue streets, North Sydney. Three months have elapsed since that date, and the object of this article is to describe what progress has been made.
During the last three months all the houses required to enable construction to proceed, 34 in all, have been sold by auction and have been demolished by the purchasers, and on the sites thus made available excavation work has been pushed on, as will be seen from the pictures.
Back to the “New Station”
AS the main northern pier of the bridge will come where the present Milson’s Point Station is, arrangements have been made to divert the railway traffic from this station to the new station already constructed on the foreshores of Lavender Bay. The station will be reconstructed so that the railway passengers will walk off the platforms to the ferry, as at the present Milson’s Point station. The tramway traffic will also be diverted to the new station, and connected with the ferry there. A short length of tramway will be constructed from Alfred-street along Dind-street, and will terminate above the new station in Glen-street. To connect the tramway passengers with the ferry a bridge over the railway, 30ft wide, will be provided, the harbour end of which will terminate 35ft above the ferry wharf. To negotiate this 35ft to and from the ferry a nest of three escalators, each 4ft wide, of the reversible type, having a capacity of 9000 passengers per hour, will be installed, and later on utilised at Kirribilli station. Stairways and a lift will also be provided. Tenders for the escalators have been let, and they are to be installed by June 30.
Installing the Power
A COMPRESSOR house has been erected at the site of North Sydney Station, and a second between Euroka-street and Ancrum-street. Three compressors have been installed, electrically driven, each by a 75-h.p. motor operating on three-phase current, 25 cycles at 440 volts. Each compressor cylinder is 14in diameter, 12in stroke, and working at about 200 revolutions per minute: each machine inducts 464 cubic feet of free air per minute from the atmosphere, compresses it to 100lb per square inch, and delivers it to the air-receivers, from whence it is conducted by 3in pipes to the air-driven jack-hammers, which drill the holes in the rock preparatory to blasting. The compressed air at 100lb pressure acts on the piston of the jack-hammers, the steel drills strike rapid blows on the sandstone, and cut into it at a rate of one foot per minute. The drill steel is hollow, and water is fed through the centre of the drill to clear the hole of the broken sandstone and keep down the dust. The Hon. R. T. Ball. M.L.A., Minister for Public Works and Railways, accompanied by Under-Secretary for Public Works, Mr. T. B. Cooper, visited the works on September 19th and fired the first shots almost at the spot where he turned the first sod on July 28th. In less than two months the houses in the vicinity had been demolished, the machinery installed, and a store, blacksmith’s shop, and transformer house erected. In the transformer house alternating current at 6600 volts is transformed to 440 volts before it is fed to the motors.
On September 19th the writer switched on the current to No. 1 compressor and set the machinery in motion. Three compressors are now in operation. When the current is switched on the throb of the compressors, the quick, sharp chatter of the drills, the hiss of the escaping air indicate that construction has begun, and after a century of waiting Sydney and North Sydney are now being joined with steel and stone. After the holes are drilled in the rock they are charged with lithyte, the firing wires adjusted, the holes tamped with earth and covered with heavy rope mattresses to prevent the debris from flying high after the explosion. The traffic in the vicinity is then warned by means of red flags, the call “Fire, Fire, F-i-r-e!” warns the workmen to get to cover; the powder monkey connects the wires to the firing battery, presses the “trigger,” and immediately the rock heaves outward and upward, carrying the mattress skyward. North Sydney reverberates to the dull roar of the explosion, and a few of those paying the bridge tax may perhaps realise that some of their money is “going up” in fire and smoke and non-political thunder. The geological formation of centuries is destroyed in seconds, but its scope of usefulness is to be extended. After the rock is dislodged it is spalled into pieces which can be man-handled, loaded into drays or motor-lorries, and either dumped at Lavender Bay to extend the park area there or tipped at the head of Berry’s Bay to reclaim some low-lying Government land. As the work progresses a crusher will be installed, and the sandstone rock broken into concrete metal for the retaining walls and tunnel linings.
Two Local Bridges
TWO reinforced concrete bridges are to be constructed – an arch railway bridge carrying four lines of railway over Euroka-street and a girder roadway bridge carrying Bank-street over the four lines of railway which pass under Bank-street, and thence in tunnels 22 chains long, emerging at Miller-street, at the site of North Sydney station. The excavation for the foundations of the arch across Euroka-street is completed, and the first concrete was poured in the abutments on October 24th.
It is evident from the foregoing that Mr. Bradfield has amply fulfilled the promise he made on July 28th last at the turning of the first sod. To most people it would appear that the work of successfully starting a railway approach involving the sum of £300,000 would be sufficient to absorb the energies of any one man, but Mr. Bradfield has also had responsibility for the city railway construction – a £5,000,000 work: has dealt by cable and letter with firms overseas who will be tendering for the bridge, and has had many interviews with representatives who are in Sydney. He has found time to assist the Lord Mayor’s conference in originating a scheme for the development of the streets of Sydney. His quiet driving force and power of origination and organisation have helped him overcome all obstacles.
Bridge Notes
(By J.K.)
SIR JOHN HUNTER, of the firm of Sir William Arrol, Glasgow, has arrived in Australia to make the necessary inquiries pending a tender for the construction of the bridge. There is naturally a sentimental hope that the work may fall to a British firm, but the Government has made no secret of its intention to adopt a policy of “a fair field and no favour.” The time for tenders has been extended into the new year in order to meet the convenience of firms who are competing for the job. The bridge will mean a lot of work for Australian firms and workmen, but the firm that is successful will have to bring out certain experts. There will doubtless be excited thousands of citizens on the foreshores when the centre span is being lifted into position. The contract states:-
“The suspended span may be built in position, or floated out and hoisted into place. The contractor shall provide all steam tugboats required to tow and control the tow of the suspended plan to the bridge site. The contractor will also have to furnish all labour, together with all scows, false-work, cables, anchors, tackle, or other plant or material that may be required to properly execute the work and must assume the entire responsibility for the satisfactory carrying out of the floating and hoisting operations. The Minister will, during such times, and to such an extent that the Chief Engineer considers necessary, stop navigation on the stretch of water required for the floating operations.”
It will be years before that memorable event. In the meantime, Mr. Bradfield is one of the busiest men in Australia. How he contrives to do his work in connection with the bridge, at the same time prepare a town-planning scheme for Sydney that the City Council and its experts have been unable to flaw, and also carry on his scheme for city railway extensions, is baffling to the ordinary person. A fine scholar and a great engineer, he is also one of the most modest men in the community. The valuable work done by Miss Kathleen Butler, of his department, in connection with the bridge will some day make an interesting story.
