Ship launching - the "guillotine"
From Practical Construction of Warships, Newton, R.N., Longmans, Green and Co. 1941. This diagram elaborates on a query posted on MarHst-l (December 2013) in which Dr John Harland wrote that "without ducumentary proof" he was fairly certain that the "guillotine method" referred to the method of triggering the launch of a ship. As far back as the days of the sailing
warship, a heavy 'dog-shore' was placed diagonally, sloping up and shorewards. This engaged a 'dog-cleat' on which was part of the forward cradle. After all other impediments to sliding down the ways were removed, the dog-shore remained the only thing preventing the launch. A sharp blow knocked it down, and away she went.
As ships increased in size, dog-shores were placed on both sides, a sledge-hammer was no longer an option, and sufficiently heavy 'dog-weights' were used. These were dropped from a height ... hence the reference to the guillotine.
The 1st edition mentioned above of Newton's book was printed on "wartime" paper, with a second edition (1955) which had exactly the same illustration but on better paper,
more suitable for scanning. The one shown here is from the 2nd ed. We hold both editions.