42
EXPLANATION OF THE PLATES.
traverse on a sweep; ‘Flamer,’ 492 tons, 120 horse-power, and ‘Firebrand,’ 492 tons, engines 120liorse-power, Mediterranean packets; (the ‘ Firebrand’ afterwards became the Admiralty yacht;)‘Medea, ’ 843 tons, engines 220 horse-power, war steamer; ‘Firefly,’ 549 tons, engines 140 horse-power, and ‘Spitfire,’ 553 tons, engines 140 horse-power, Mediterranean packets; and ‘Ionia,’ 263tons, engines 90 horse-power, packet for the Ionian Islands ; all which are built on the same mode ofsecurity as the * Medea, ’ and have proved to be excellent sea boats, possessing speed, ease, and comfort,combined with superior strength of fabric.
The PLATE marked 4 should be placed to follow Plate XXXI.
{See page 21, and the List of Plates.)
The engines, two of 60 horse-power, were by Messrs. Boulton and Watt, and the vessel was builtbv Messrs. Fletcher, Son, and Fearnall, London ; launched 28th March, 1835, for the Herne Bay SteamPacket Company.
PRINCIPAL DIMENSIONS OF THE HULL.
Length between the perpendiculars.
Breadth to the outside of the bottom plank.
Depth at shaft from top of floor timber to the under side of deckBurthen in tons, 376|T (builders’ measurement).
ft. in.154 022 410 4
This vessel was constructed for the conveyance of passengers and luggage to and from London to Herne Bay with the greatest possible despatch, and comparing her displacement and power withother similar vessels, was then the fastest running out of the Thames . This superiority of speed waschiefly effected by a novel mode of building, a mode combining the fourfold advantages of increasedbuoyancy, a more uniform diffusion of strength, prevention of rot by exclusion of surfaces, and affordingthe greatest possible facility to repairing.
The bottom, or that part of it on which the engines and boiler were fixed, was composed of stout floortimbers going from bilge to bilge, placed close together and dowelled and bolted to each other, andplanked externally with the best well-seasoned four-inch Dantzic deals, fastened in the usual manner; butabove, before, and abaft this part of the bottom so wrought, the timbers of the frame used in commonwere omitted, and the plank continued of the same thickness to the top of the sides, having the edgesgrooved and tongued, and secured to each other by f-bolts driven through the edges in a diagonaldirection at about 15 inches apart; in addition to which, long diagonal iron plates, 4 inches broadby fths of an inch thick, placed at an angle of 65°, and 2 feet 6 inches from each other, were workedeach on a Dantzic fir plank 2 } inches thick and 9 inches broad, the whole secured by a through-bolt ineach outside strake, having a screw point and nut setting up on the diagonal plate inside the vessel.
It must be obvious to all persons acquainted with the nature of ship-building, that the hull of a vesselso built would offer the greatest advantages to the caulking, requiring but half the usual quantity ofoakum, and that stopped from being driven through the seams by a strong oak tongue bedded inwhite-lead uniting the edges of the planks. The uniform strength of the entire hull exceeded allexpectation.