The 21th Imrovement
Consists in forming the lower mast out of four spars pyramidically placed in
the vessel -- their bases rest in the hold on cross-steps, which extend
several feet across the keelson, and the pyramid tapers gradually to the
mast-head, where the four spars meet, and are braced together by the
trussel-trees and cap.
By this plan the masts and rigging might be secured without throwing any
pressure upon the sides of a ship -- for as every one of the four spars
passes through the deck, and is fixed to a step in the lower part of the
ship's hold, their is no pressure elsewhere than upon the ship's keelson and
Shipwreck and Collisions at Sea greatly prevented by Christophers' Patent Improvements in Naval Archtecture. With four plates.
London: J. Olliver, 59, Pall Mall; P. Richardson, 23, Cornhill. Liverpool: Deighton & Laughton. M.DCCC.L. 8vo, (4), 112 p, 4 pl.
Sjöhistoriska Samfundet |
The Maritime History Virtual Archives.
Copyright © 1996 Lars Bruzelius