| Summary: | bavin APPENDIX. 27 time of firing the ship, blows out the port lid, and opens a passage for the flame. Immediately under the main and fore shrouds is fixed a wooden funnel, whose lower end communicates with a fire barrel,* by which the flame passing through the funnel, is con- ducted to the shrouds. Between the funnels, which are likewise called fire trucks, are two scuttles, or small holes in the upper deck, serving also to let out the flames. Both funnels must be stopped with plugs, and have sail cloth, or canvas, nailed close over them, to prevent any accident happening from above to the combustibles laid below. They are primed with a small piece of quick match thrust through their vents into the powder, with a part of it hanging out. When the ports are blown open by means of the iron chambers, the port lids either fall downward, or are carried away by the explosion. * The fire barrels ought to be of a cylindrical form, as most suitable to contain the reeds with which they are filled, and more convenient for stowing them between the troughs in the fire room. Their inside diame- ters should not be less than twenty-one inches, and thirty inches is sufficient for their length. The bottom parts are first well stored with short double dipped reeds placed upright; and the remaining vacancy is filled with fire barrel composition, well mixed and melted, and then poured over them. The composition used for this purpose is a mass of sulphur, pitch, tar, and tallow. There are five holes of three quarters of an inch in diameter, and three inches deep, formed in the top of the composition while it is yet warm; one being in the centre, and the other four at equal distances round the sides of the barrel. When the composition is cold and hard, the barrel is primed by filling those holes with fusee composition, which is firmly driven into them, so as to leave a little vacancy at the top to admit a strand of quick match twice doubled. The centre hole contains two strands at their whole length, and every strand must be driven ...
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