A Ton-Mileage Memory

Gauging narrow boats, copper gauging plate, Taylor's yard, Chester Canal Heritage Trust, Shropshire Union boatyard, Ellesmere canal

From the start canals were designed to carry cargo and from the start they were expected to earn their living by charging the boatman or bargeowner a toll for all the tonnage carried. The enabling Acts of Parliament usually specified maximum charges for specific goods, with lime and manure usually carried at a cheaper rate for the general benefit to agriculture and the population.

Goods were to be charged at so much per ton multiplied by the mileage. (On the Ellesmere Canal, for example, coke, limestone and rock salt were charged at a penny ha’penny per ton-mile, timber, slate, bar iron and lead ore at tuppence, but all other goods, wares and merchandize whatever was to be at three pence per ton-mile. But dung, soil, marl and ashes to be used for land improvement were exempt). Calculating the mileage was easy, for the distance to each wharf and warehouse was already known and marked up on distance tables, but how could one be sure of the tonnage carried? Clearly the canal company needed a system that could tell exactly what tonnage a boat was carrying (and the customer would also quite like to know that he was receiving the same tonnage at the end of the journey as was loaded at the beginning). What developed were various systems of ‘gauging’ boats, judging the tonnage carried by how low the boat was loaded into the water but these systems had to be accurate to half a ton or so to be useful. Latterly it was done by a man with a big ruler, either measuring the draught on either side fore and aft, or measuring the dry side still out of the water in the same way. These measurements were added together, then divided by four to get an average figure which would, in turn, be checked against a published list, where each individual boat’s tonnage per inch was documented. It worked but it was a bit clumsy and depended on every check station having an up to date indexing book to refer to. But in earlier times, perhaps when wooden boats were much more prevalent gauging markers were fixed on or cut into the boat itself.

My attention to this little bit of esoteric canal history has been focussed by some discoveries recently made at the old Shropshire Union boatyard in Chester, more recently known as Taylor’s Yard (for over sixty years!) A group of volunteers under the leadership of the Chester Canal Heritage Trust have been surveying some of the old buildings prior to forthcoming repairs, cleaning them out and recording any surviving items of boatyard history. I have been part of the team and it has been a fascinating if mucky job. My personal highspot was the discovery of some sections of copper strip, lost in a hole in the floor and subsequently covered and hidden by a section of steel plate, the remnant of some repair job in the distant past one assumes. I could see some numbers stamped into them and thought I recognised them as pieces of a gauging plate from a narrow boat. I have only ever seen one before but there is a very good description of them in Edward Wilson’s book The Ellesmere and Llangollen Canal published by Phillimore and Co. back in 1975. With the permission of the publisher I would like to quote from his book here because it all suddenly seems to make more sense. Edward Wilson was a schoolmaster who lived for twenty years next door to the canal maintenance yard at Ellesmere in Shropshire. Here there was a dry dock for boat maintenance presided over by old Mr Moody the boat builder, son and grandson of previous boatbuilders at the yard and it is clear that Wilson drew much of his information from Mr Moody’s reminiscences. From the dates of photographs included in the book we can deduce that he was taking his notes in the early 1950s.

“Tolls were levied by the canal company on the weight and nature of the cargo carried, and all boats had to be ‘indexed’ to make it easy for this weight to be determined. The method of indexing used today differs from that used in the past.” (my emphasis) “Mr Moody, who has a notebook recording the indexes of some 50 boats, recalled the older method.

The boat to be indexed was brought empty into the water filled dock, and vertical grooves were made in the hull at the bow, amidships and stern on each side to accommodate laths; these were lightly nailed in position. Four heaps of large rectangular iron weights were piled alongside the dock, where there were two cranes each of which could pick up weights from two of the heaps. Each crane lowered two tons, consisting of three 600lbs weights and one 440lbs. weight for each ton; thus four tons were added altogether, spaced out equally along the length of the hull. Marks were then made on the six laths at water level. Further four tons of weights were added, and marks made, until the boat held 28 tons of weights.

The weights and the six laths were removed and the four ton markings subdivided to give one ton markings. The permanent markings were made on copper strip, by placing lath and strip side by side and stamping the figures from one to 28 tons, using a special series of steel stamps. The six numbered copper strips were then fastened to the hull in the grooves already present. There were six of them to obviate any difference which might be due to uneven loading resulting in the reading at one end being too high and that at the other end being too low; by taking the average of the six readings an accurate reading was bound to result.”

Well, cleaning and close inspection of the sections of strip recovered from the floor at Chester show them to be exactly as described by Edward Wilson both in his writing and the neat little diagram that he also includes. As Ellesmere was possibly the main gauging dock for all the Shropshire Union narrow boat fleet it is quite possible that they were stamped with the very same number punches that still remain at the maintenance yard today. And by a pleasant piece of poetic justice the last few remaining indexing weights from the Ellesmere gauging dock are now acting as historic ballast in the hold of the restored Shropshire Union fly boat Saturn. Heritage research can be a beautifully rounded concept at times, can’t it?

©Tony Lewery, The Brow, Ellesmere,
November 27 2008

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