A Tale of a Viaduct

This the old viaduct near Perth, constructed in 1869*, and one of only two railway viaducts in Tasmania. It’s known as the Flinty Creek Viaduct or Hunter’s Mill Viaduct. Alas, of the mill and its successor there is no sign.

This is the mill around 1910, if you’re interested.

But to the viaduct. A railway in Tasmania was one of those things talked about for many years, but never got off the ground. An example form 1846:

A company in London have put forth the following prospectus for a railroad between Hobart Town and Launceston:
From Hobart Town to Launceston (V.D.L.) provisionally registered, previous to the date of the late standing orders of the House of Lords. In a few days the projectors will be prepared to submit to the public a plan for more closely connecting these two important towns by means of a railway. Any information may be obtained by application to Messrs. Fyson and Curling, solicitors, No. 3, Fredericks place, Old Jewry ; or to the Provisional Committee, at their temporary offices, No. 54, Old Broad-street. (Provisionally registered, previous to the date of the late standing orders of the House of Lords.)
When the railroad mania has come to this, it must be upon its last legs.

Colonial Times, 6 February 1846

The locals weren’t impressed by the idea.

The project entertained in England a few months back of forming a railway across our rugged and mountainous island, was conceived in ignorance of the surface over which it was to have been carried, and by parties who had never seen the colony.
Letter to the Editor, Launceston Examiner 13 June 1846

Over the years, the idea of a railway network, particularly connecting the major centre of Launceston and Hobart, was often discussed, but you know, there land would have to be obtained, labour is hard to get, and the need wasn’t there. Enter the Launceston & Western Railway Company, formed in in 1867 to build a railway from Launceston west to Delorained. Their lines opened in 1871 (and the government in Hobart decided it did actually want a railway too, and the Launceston to Hobart Main Line was built, by the lowest ibdder of course, and opened in 1876, )

From a progress report on the progress of the L&WR line:

Out of 58 culverts, 47 are now complete; 700 iron drainpipes have been laid out of a total of 700. There are 12 large wooden bridges included along the line, and of these 11 have, been finished, and one only remains to be erected. There are two very extensive brick viaducts, one at Longford which is finished, and one at Hunter’s Mill, which it is expected will be completed, within three weeks. The great iron and brick bridge over the South Esk River, is in a condition of forwardness, and is in fact ready for the, reception of the iron work on arrival.
Launceston Examiner, 26 August 1869

And so, as I mentioned earlier, the viaduct at Hunter’s Mill is the one just outside of Perth. The one in my photo above!

This is a very pretty bridge plainly built with brick, having four spans each 40 feet, and rising to a height of 42 feet from the ground level. The bricks of which it is constructed were made at. Longford, we believe, by the Contractors, and visitors to the works on Thursday last were not a little surprised at the quality of them, as compared to these used for ordinary building in the colony. This bridge is one of those works on which tho Engineers have dispensed with every unnecessary expense, it has no stone dressings, but Mr. Doyne has endeavoured to produce a very pleasing and beautiful effect, by simply attending to proportions and contrast of colour which he obtains by selecting tho bricks for the several parts. Tho piers, abutments, and spandrils are all built of bricks of a somewhat dark color, owing probably to the presence of a little iron in the clay ; while tho arches and other portions are constructed of the lighter colored bricks, and to heighten tho contrast still more tho joints are simply rough drawn in the case of the dark bricks while in the light they are raked out and filled in with white putty.

Mercury, 25 August 1869

Hunter’s Mill Viaduct.
The whole of those works are finished with the exception of the pointing to the soffits of some of the arches. The centres of the arches were struck, and the fourth was eased. I could not detect any sign of settlement in them. They are well and substantially executed, and the whole is built with lime mortar, except the arches and coping, which are in cement.

Mercury, 16 October 1869

The Launceston Viaduct was originally estimated to cost £6000, but it cost in reality £25,000 In looking into the matter it was found the structure was a magnificent one, and perhaps it was a wise expenditure.
Mercury, 18 October 1869

And if you’re interested, this is the Longford viadcuct:

Here the valley of the South Esk, and the river itself have to be crossed, the distance being about half a mile, and this object is accomplished by means of a brick viaduct, a magnificent iron bridge, two trussed wooden bridges, and four embankments. Those works are all very heavy, indeed, this is the most expensive point on the line. The embankment which joins tho brick viaduct is nearly 29 foot from the ground at the deepest point. The viaduct or bridge has five spans each of forty feet, and it is built of brick, much after tho same design as the Longford viaduct; the arches are, however, flattened more in the roof, in order to afford a wider opening for the flood waters which sometimes swell the South Esk to immense proportions. Here again groat pains havo boen taken by tho Engineors to obtain a lovol abovo the floods. The highest points roachod by tho heaviest floods woro ascertained, and an ampio spaco allowed abovo that. The Longford viaduct is built on the same principio us that at Hunter’s Mill and, if anything, it is the stronger of the two. The foundations are from twenty-four to twenty-five foot below the surface of the ground, and about as many bricks are thus buried in the soil as appear above it. A more substantial piece of masonry does not exist in the Southern Hemisphere, and it is well worth inspection on the part of those interested in building.
Mercury, 25 August 1869

And the bridge:

The iron bridge crossing tho South Esk River is, however, the work most likely to attract the attention of visitors, it is to have two spans each of 200 foot, and is after tho design known as the continuous girder bridge, fixed in the centre, but expanding and contracting at both ends. Mr. Doyne is tho inventor of this particular style of bridge, and for it has obtained distinction in England. We cannot enter into any minute description of the structure, nor anticipate what its appearance will be, but we hope ere long to have an opportunity of visiting and describing it, whom complete. The foundations for the iron bridge are now finished and a ponderous wooden staging (a bridge in itself), has been put up, on which to erect it, and as soon as tho iron-work, now on its way from England arrives, the work will be proceeded with. The foundations intended for the reception of the iron girders are pronounced by every professional man who has seen them the greatest piece of masonry in Tasmania. They are embedded 27 foot below tho river level, and composed of ponderous blocks of hard blue stone, dove-tailed together, and faced with brick and free-stone. Tho form of these foundations or piers is known as the outwater, and they present to the force of the current a sharp front like tho prow of a vessel. Thora can be little doubt that when tho iron bridge over the South Esk is erected it will rank among the greatest works in Australasia
Mercury, 25 August 1869

(From the Tasmanian Archive & Heritage Office.)

William Doyne, who designed four bridges over and along the South Esk, was a pioneer in railway and bridge engineering and construction, and respected throughout Europe and Asia. Doyne first came to Tasmania in 1861 to do the initial surveys for the Launceston and Western Railway, and designed and oversaw the construction of King’s Bridge. He reflected the 19th century philosophy that major projects should be aesthetically pleasing, as well as functional. Integral to his iron bridge design at Longford were magnificent cast-iron pillars at each end. The bridge was greatly admired for a century afterwards. Around 1967 the famous pillars at each end were removed as construction of the Poatina hydro station required huge turbines to be transported by rail, and there was insufficient clearance at the bridge.
Examiner, 10 May 2020

* On the Internet, it often said to be 1868. This might be because there’s a information panel beside the road that says, in part, “The viaduct is part of the Launceston and Western Railway, which was opened by Queen Victoria’s son, The Duke of Edinburgh, who turned the first sod on January 15th, 1868”.

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