Full Steam Ahead: How the Railways Made Britain. Peter Ginn
a tree down to make way for a railway is only half the story. The real problem is the stump. Victorian stumps were usually a lot higher than modern tree stumps, because of how a two-man saw was used. However, even if the stump was cut down to ground level, laying track over the top of it would only result in serious problems later on, when the stump rotted out or the tree tried to grow back (often from the roots).
In market gardening, tree stumps were often removed mechanically or by the use of an explosive such as stumping powder or dynamite. The navvies working on the permanent way were more likely to dig down into the ground around the stump, set a fire and smother the whole thing in leaf litter and earth. The result would be a clamp that would burn the remaining stump into charcoal. This could then be used as fuel for blacksmithing or simply for domestic fires. Although many trees were cut down to meet the demands of the railways, no part of the tree was ever wasted.
Once our tree was on the ground, we could get round to processing it. The first job is to remove the branches and is known as ‘snedding’. The trunk can then be cut into sections, with the objective of obtaining as many nine-foot sleepers as possible firmly in mind. To cut the trunk sections into sleepers, we used Britain’s only working water-powered saw mill, on the Gunton estate in Norfolk, just outside Cromer.
“IN MARKET GARDENING, TREE STUMPS WERE OFTEN REMOVED MECHANICALLY OR BY THE USE OF AN EXPLOSIVE SUCH AS STUMPING POWDER.”
Peter and Alex stand over the felled tree. A two-man saw necessarily leaves quite a high stump. This then needs to be removed.
The beautiful rural setting of Gunton saw mill near Cromer, Norfolk, which is still in operation to this day.
Built in 1824, just before Britain’s railway bonanza, by the third Lord Suffield, the saw mill is a remarkable building housing a remarkable piece of kit. It was originally intended to be used as a processing plant for all of the estate’s timber, and just outside the doors of the building are the remnants of hastily poured concrete that represented the additional two circular saw pits made by the allies during the Second World War.
However, by the mid-1970s the building had completely fallen into disrepair. The thatch had started to rot, there had been a fire, and the two-and-a-half ton cast-iron flywheel had fallen from its mountings. The Norfolk county council, the local windmill trust and industrial archaeology society collectively drew up plans. With the help of the last remaining tenanted Harbord family member, Doris – and after her passing, the estate’s new owner Mr Kit Martin – the water-powered saw mill was saved.
When Alex and I first entered the building, he noted the recently thatched roof. Between the thatch and the rafters was a layer of woven reeds – known as ‘fleeking’ – that Alex commented upon. I told him that I had once lived in a thatched building and it too had been f-ing leaking…!
An ancient rural water wheel and mill with a substantial water source in the foreground.
One of the notable aspects of the Gunton saw mill was just how dry the building was inside considering that there were two huge water wheels at the back. The sides of the building are wooden slatted panels that can be removed to increase light and more importantly to create an opening through which the tree trunk to be processed can be passed. I found the hardest aspect of the whole process to be moving the trunk from the yard outside to the saw bench. We used block and tackle, which through a series of pulleys gives the rope being pulled a mechanical advantage. We hauled the log in and got it set on the bench. After that, the saw mill did all the work.
The water power for the saw mill comes from a man-made lake that covers close to forty acres. We lifted the sluice gate and filled the headrace that channels the water onto the wheels inside. There are two wheels, one to drive our saw and one to power a grain crusher. They idly turn just on the water that leaks through the gaps. The benefit of this is that it stops the paddles of the wheel drying out and splitting and prevents an imbalance in the wheel between a wet and a dry side. A sluice gate for each wheel that regulates the flow of water is operated from inside. These effectively act as throttles for the wheels, but even when we fully opened the gates and had the wheels turning at full pelt, there was very little noise.
A powered frame saw of the type that would have been used for cutting wooden railway sleepers in the nineteenth century.
The wheels are ‘breast-shot’, which means that the water hits the paddles of the wheel at about the height of the axle and runs underneath the wheel. Early water wheels tended to be ‘undershot’ wheels, which sat on a stream or a river and utilized the kinetic energy. The most powerful water wheels are ‘overshot’ wheels, which use both the kinetic and gravitational potential energy of water flowing into them. Breast-shot wheels are found in places like Gunton, where the landscape does not naturally provide a height advantage. However, the funnelling of a huge millpond into a narrow millrace changes the pressure created by the weight of the water into velocity.
The saw itself was exactly the same as a pit saw, except instead of being worked by two people – one standing at the top and the other at the bottom – this saw was fitted to a large frame that moved up and down. We only had one saw in place, but when cutting planks it was possible to fix multiple saws at set distances. The key was to make sure that they were all exactly aligned.
As the saw moved up and down, the gearing designed by a clock maker could be engaged. Similar to an escapement mechanism in a pendulum clock, this periodically turns an axle attached to two pinion gears, which moved two racks attached to the underside of the frame upon which the log to be cut was chained. This moved the log through the saw a fraction of an inch at a time. As the log passed through the saw, the chains and the cross-struts of the frame were removed and re-attached so that the saw only cut the log. This was relatively straightforward, but nevertheless we set the saw at the lowest speed. I was told it was frightening when the saw was going at full pelt.
Just as with a pit saw, as the log went through we tapped thin wedges into the cut to open it up and stop the wood biting the saw. However, unlike a pit saw, we did not need to chalk a line for the cut. Instead, plumb bobs were used to eye up the cut of the saw, but once the log was strapped in their was no deviation to the cutting line. When a log is first put on the frame to be cut, it is strapped to a plank to give it some stability. Once a face has been cut, the log can be turned onto it and it becomes steady.
These water-powered frame saws were reasonably common throughout Europe and there were a number in Norfolk. However, pit saw workers did not welcome them, because they rendered many men redundant. They were also short lived, because circular saws took over and steam power followed by diesel and electricity became the power sources of choice. The mill at Gunton survived because of its position on an estate isolating it from the outside world and because it was never taken over commercially.
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