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January 8, 2007

The Tolmer's Tackle

(This method for tightening a rope without a block and tackle is from the November 27,1952 edition of 'the Scout'- a weekly Scouting newspaper from the UK. John Sweet's original text describing the tackle follows after the drawing.)

"White Owl" of Stoke Newington, has reminded us that some time ago we wrote a piece in 'Scoutward Bound' about unorthodox rope tackles for applying strains to heavy ropes when no blocks, etc. are available.

"White Owl's" particular problem was to construct a Gamekeeper's Bridge across the tank trap at Tolmers, the I.H.Q camp site in Hertfordshire. The foot-rope consisted of a 7 inch hawser, and as the total span was pretty considerable and the only available manpowers two Rovers plus himself, "White Owl" realised that something quite out of the ordinary was needed.

Here is his description of how the job was tackled:

"The main ropes was secured to a tree at one side of the tank trap and tied off to a second tree on the farther side. Two fairly strong ropes were bent on to the hawser about half-way down its length and made fast under strain to convenient trees (C and D), as shown in the diagram.

Two lighter heaving lines were clove-hitched to these secondary ropes (F and G) and pass over and round the ropes on the opposite sides of the hawser and brought back to the side on which they were secured.

To operate the tackle, my two Rover assistants hauled in simultaneously on their heaving lines, thereby springing the three ropes together, whilst I applied a whipping, starting at point E and working upwards at each new heave. The clove-hitches were slide farther and farther up the hawser towards the anchorage as the strain increased.

This had the effect of moving point E slowly but surely towards the anchorage B, and we were able to take up the slack in the hawser between E and B on the anchorage itself. When the job was finished (it took time!) a load of about 224lb. in the centre of the bridge caused only a three-inch sag."

Well, there you are. You will never find the Tolmer's Tackle in the book, but it was found in practice to be efficient.

How about your Patrol trying it out?

Mind you, I am all in favour of using the orthodox methods whenever possible, but pioneering is meant to be an adventure and so long as you don't take undue risks there is no harm in experimenting with ideas of your own.

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