More joy from our photographic archive, courtesy of Volunteer Alan Clarke…
Heath Robinson Garden Waterer Contraption
The above photograph comes from the Austin Underwood collection. The only text on the envelope, which contains a series of 2¼ inch black and white negatives, is “April 1965 Nether Wallop”. The Wallop Brook flows through this village. There has been a mill at Nether Wallop for over a thousand years, as one is listed in the Domesday Book. Thus, I deduce that the residents of Nether Wallop are well acquainted with water wheel technology.
This photograph of a water wheel rewards detailed examination. I use the term Heath Robinson to describe its construction. I define a “Heath Robinson contraption” as a machine built using ingenuity and whatever is to hand, often string and tape, or unlikely cannibalisations. Apparently the term is linked to Second World War Britain’s shortages and the need to “make do and mend”. This photograph shows a motorcycle wheel in the centre with eight long rectangular blades attached. There have to be enough blades so that one blade is always in the water, otherwise the wheel will stop, as with no blade in the water there is no force to keep the wheel turning. Eight is about the minimum number of blades necessary.
Now for the interesting bit: the diameter of the wheel. The purpose of the wheel is to provide a head of water of about five feet. This is done by having small tin cans pivoted near the ends of each blade. These are filled as the cans are dragged through the water. The cans are then rotated up to the top where a hot water bottle is used to gently rotate the can and empty it into a container, which then allows the water to flow away through an almost horizontal drainpipe, going out of the photo to the right. It is quite ingenious to use a soft hot water bottle to avoid a continuous clanking noise. Austin has cleverly taken the photograph when a can is being emptied, so one can see the water flowing out of the can. This also shows the direction the waterwheel is rotating, counter-clockwise looking into the photograph. I can’t claim to understand all of this ingenious construction. The hot water bottle appears to be attached to a vertical pole which can be raised or lowered a very fine amount via a horizontal lever just above the river surface. Perhaps this was found necessary, as the force to turn a full can at the top might be enough to stop the wheel if the brook flow was weak. By lowering the hot water bottle, the can would not be completely turned and thus require less force. If the hot water bottle was lowered enough then the can wouldn’t be turned at all, and thus not be a brake on the wheel at all. Hence maybe the need for fine adjustment depending upon the brook flow.
If any reader of this blog has access to a small brook, they now know how to make a garden watering contraption which requires no electricity.