Bruce Comfort
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I'm a retired engineer. I ride a 400cc Suzuki Burgman motorscooter and I live in Oamaru, South Island of New Zealand. I have two adult daughters. My interests (if you haven't worked it out) include New Zealand's heritage of engineering works, snapshot photography of the built environment and recording pastoral farming activities around here. ---------------------------------------------------------------------------------------------------------------------- PLEASE NOTE THAT MANY PHOTOGRAPHS ON THIS PANORAMIO SITE HAVE BEEN TAKEN BY ACCESSING HERITAGE BUILDINGS, STRUCTURES, AND ENGINEERING ARTIFACTS WHICH LIE ON PRIVATE LAND. PUBLICATION OF PHOTOGRAPHS ON THIS SITE DOES NOT IMPLY ANY PUBLIC RIGHTS OF ACCESS. ---------------------------------------------------------------------------------------------------------------------- PLEASE ALSO NOTE THAT A FEW PHOTOS ON THIS SITE ARE NOT MINE, AND THAT MANY ARE TAKEN INDOORS AND ARE OF MACHINERY AND THAT THIS APPARENTLY CONTRADICTS THE TERMS OF USE OF THE PANORAMIO WEBSITE. I HAVE HAD THE SITE MODERATORS' APPROVAL FOR USING THE SITE THIS WAY AS ALL SUCH PHOTOS LINK IN SOME FASHION TO MY OWN PHOTOGRAPHS OF PLACES IN NEW ZEALAND WHERE ARTIFACTS OF ENGINEERING OR PASTORAL OR INDUSTRIAL HERITAGE CAN STILL BE FOUND. ---------------------------------------------------------------------------------------------------------------------- MY INTENTION IS NOT TO USURP THE RIGHTS OF THE HISTORIC PHOTOGRAPHERS NOR OF COPYRIGHT OWNERS, AND CREDIT IS GIVEN WHERE I CAN. I have made an endeavour to contact copyright holders of material published on these pages and where appropriate, permission is still being sought for these items. Where replies were not received, or where the copyright owner has not been able to be traced, or where the permission is still being sought, I have decided, in good faith, to proceed with publication. I would be happy to hear from copyright owners at any time to discuss usage of item. IF YOU GO TO THE PLACES WHERE MY OWN PHOTOGRAPHS HAVE BEEN ACCEPTED BY THE MODERATORS TO BE IN THE PHOTOS LAYER ON GOOGLE EARTH, MY HOPE IS THAT THE OTHER HISTORIC PHOTOGRAPHS (which will not have been accepted by the moderators of Google Earth but which appear on these pages) WILL STIMULATE YOU TO THINK ABOUT THE ENGINEERS, ENTREPRENEURS, INVESTORS, THE WORKERS AND OPERATORS AND ALL THE PEOPLE, NOW GONE, WHOSE LIVES WERE INEXTRICABLY TIED TO THESE PLACES AND THESE ENDEAVOURS. ---------------------------------------------------------------------------------------------------------------- MY E-MAIL ADDRESS IS guyro@slingshot.co.nz AND I WELCOME INPUT INTO THIS WORK -----------------------------------------------------------------------------------------------------------------

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The contract for the delivery of the timber for this aqueduct to site from the nearest railhead calls for the "transport of 60,000 board feet of Kauri from Pakakaio Junction (now Pukeuri) to Rocky Gully" The timbers in this view are substantial. The weight of timber in the structure was nearly 50 tons and it held nearly 70 tons of water when full.

The tallest of all the aqueducts (but not the longest) this aqueduct developed a sag early in its life and until the 1940s was supported on auxiliary trestles. It was replaced with an inverted syphon of 24" diameter concrete pipes in the 1960s and subsequently left to fall down of its own accord. Before that occurred however, people had salvaged nearly all the long wide and thick Kauri planks which the flume was made of. These were remarkable pieces of timber - shipped, as was all Kauri, from the Coromandel or Great Barrier Island or the Waitakeres - machined in Oamaru (we must presume) and installed with a tongue and grooved system to render the flume water tight before thick layers of pitch were applied to all surfaces not in contact with the water.

By far the most impressive artefact of the race still extant is this lovely aqueduct across a gully and small unnamed stream which discharges into Landon Creek.

It has both timber trestles and limestone piers and the limestone blocks were quarried from a small outcrop at the base of the pillars. Cut by hand saw and bolstered (chipped to make them look rounded and natural on the faces that show) the quarry has just one "spare" block in place. Frugal workmanship.

The timber for this aqueduct is a mix of Kauri, Australian hardwood and Rimu, and of course the box fluming - now all replaced, would have been 8"x2" and possibly 8"x 3" long timbers with pitch all over the outside and all over the trestles.

In 1880 nails were generally made by hand. Some of the nails used in the race aqueducts can be found in the pieces of the Kauri planking which still survive around the Waitaki District in sheds, culvert, garden edges and pig-sties. They are big and square in cross section with button forged heads. Some will have been 150mm long. Wooden dowels too, seem to have been used and lots of steelwork which shows all the signs of hand forming and with holes cut with drifts whilst hot (hot punched) is to be found around the bases of the dismantled aqueducts.

This spectacular aqueduct jets out from a limestone escarpment on the upstream end and the first set of limestone piers are founded on one of the benches of that escarpment. The creek runs between that set of short piers and the first wooden trestle and is some 4 metres below the foundations in a limestone gorge. The trestle looks a bit "ragged" and is certainly not in its original condition - repairs and modifications seem to have been made to it. Then there is a set of tall limestone piers and another short trestle. Along the top of the piers and trestle is a railway iron tie beam - this too is certainly not original and the original structure would have had considerable amount of big timber in the flume support structure. The top of the extant aqueduct being half round steel is pretty much self supporting whereas planked box section timber fluming is not and the whole thing would have been much more bulky at the top. There are just a few photos I have found of the original box culverting (elsewhere on these pages) and they show the huge timbers and complex structure needed to keep 30 or 40 tons of water suspended 20 metres above the ground!

What has survived of the lower structure is in reasonable condition, however this aqueduct would have been most spectacular when it was first constructed.

This photograph is taken just inside the upstream portal of tunnel 1. It clearly shows the typical (a) flat floor (b) cut and convex shaped limestone blocks lining the first few metres of (each) tunnel until the rock is stable (c) the transition to the basalt which is the core native rock of most of the hills the tunnels traverse. There is light at the end of this tunnel which is just 137 metres long.

The workmanship in these little tunnels is first rate - you are looking at an 130 year old tunnel here!

In this tunnel weeping seepage has been utilised by the current landowner to form a pond for irrigation behind a small block wall dam just inside the entrance. By using a dam just a few cm high (just visible at the limit of visibility) and the fall of this long (890m) tunnel he has created a few thousand litres of dry weather water supply from deep in the hill.

The tunnel is lined with cut and shaped limestone blocks and the construction with its flat floor is typical. Notice that the long blocks to protect the portal edges are not needed deeper in the tunnel here as any barge scraping the side here will come off worst.!

Looking across the race and downstream of the little unnamed creek it crosses the size of this little aqueduct is obvious. In the background are the mullock heaps - of rock removed from the tunnels

Here you can see the construction of the tunnel portals. What is not visible is the sense of the full height nor the floor - which was flat.

An interesting feature is the large square cross section stone which protrudes slightly into the tunnel profile at the right and just above the water line. The one to the left can be discerned through a dried weed. These blocks are long - running back some 1400mm into the tunnel.

They are there so that any vehicle such as a cart or wheelbarrow or barge (yes truly) which bumps against the portal when exiting cannot knock this stone out of the arch and dislodge all the stonework. Barge! Well, no barge ever passed through these tunnels but if you look at photos of barge tunnels from Europe and the UK you will see the design feature replicated in every case. The stone masons at Oamaru were not just good at their job but also immersed in the technology of it. There are a few engraved names in the tunnels but dates are uncertain. In this tunnel (number 2) there is a section in the centre where the rock was fractured and stonework has been erected to support the roof. For most of their length all the tunnels appear to have been in basalt.

Here the view is downstream from the exit portal of tunnel 1 across the short aqueduct to the intake of tunnel 2.

All the tunnels are excavated out of the hillsides like this one is - a large vee shaped excavation is formed back to the stable limestone or volcanic rock which underlies the yellowish Loess with the tunnel fully lined or formed with cut limestone blocks back until the native rock is sufficiently solid to sustain an unlined tunnel. The vee was fully fenced to keep stock off the steep slope, even when the race itself was not fenced. Those are modern fence posts in the view, but in places at other tunnels, some of the the original Totara fence posts still survive. The tunnels were dug by labourers employed by the construction contractor, although urban myth has it that one of the longer ones was dug by Italians and it is consequently known as the Italian tunnel. Or maybe it's the other way around. Four men were trapped in a cave-in in one of the tunnels and two did not survive. As far as I can tell these two were the only fatalities directly attributed to work on the race.

This is the second shortest aqueduct on the race. Just 12 feet long on McLeod's original drawings and between tunnels 1 and 2, like all the aqueducts it would have originally been rectangular open top box section and made from Kauri (wood) It has no intermediate supports and spans side to side over an unnamed creek which tumbles through a limestone gorge downstream. The drawings prepared by Donald McLeod for this aqueduct and the two tunnels nearby (that is the downstream portal of tunnel 1 in the photo) are derived from McLeod's very accurate and sophisticated survey plans. His drawings show the aqueduct and the two short sections of the race upstream of it out of tunnel 1 and downstream of it towards the intake of tunnel 2 - here seen lined with limestone blocks as drawn by the designer.

Had the survey been inaccurate or the construction of the race defective, this short aqueduct would have of necessity been longer - if the race was too elevated at this point or shorter (possibly non existent or at the same level as the stream which would have been very hard to deal with) had the race been set too low.

The fact that it is exactly as designed is a tribute to the surveying and the construction - considering survey instruments were quite unsophisticated in 1876 - 77 when the survey was done.

On the farm on which this aqueduct is situated is a small open fronted implement shed partly made from Kauri planks with tar on them. These planks will almost certainly come from the original flume when it was replaced by the half round steel in the 1940s.

This gate valve in the public atrium of the apartment block built in Wellington Harbour Board Shed 21 may be a valve associated with the hydraulic machinery (wool presses) which were in this building when it was a Harbour Board Wool Store. The "double dumping" of wool bales which arrived in wool stores at points of export like Wellington's wharves was a huge and lucrative business for firstly the Wellington City Council (truly - hardly what we would call core business for a local authority these days) and later for the newly constituted Harbour Board. Double dumping squeezed two relatively soft bales of wool into the space occupied by one (or less) in an hydraulic press. The two bales were secured together with multiple high tensile wires before the pressure was released. The space saving reduced freight charges and was and still is essential for shipping textile fibre of all sorts around the world. By the 1950s most of the presses in Wellington were running on electricity and oil, but in the early 20 century they ran off the Harbour Board's hydraulic network which used pressurised water.

Other such networks with water as the power transmission fluid, were constructed in London, Melbourne, Sydney and Manchester and most of these were "public networks" run commercially and from which customers bought pressurised water in gallons at 1000psi, just as today we buy electricity in killowatts at 230 volts.

The Wellington Harbour Board network was private and the Port of Greymouth too, had a small one with two or three cranes. No others are known to have been built in New Zealand.

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