The British Mars : containing several schemes and inventions, to be practiced by land or sea against the enemies of Great-Britain ; shewing more plainly, the great advantage Britain has over other nations, by being masters at sea ; to which is added, an appendix, containing a scheme for manning the British navy, with less grievance to the subject; and a scheme to employ seamen ; of a copper mine near Hudson's Bay and of discovering the North-West passage, or determine there is no such passage ; with cautions and directions . ( HI )Retreats to bring the Wall ftrait at the Surface orFoot of the
The British Mars : containing several schemes and inventions, to be practiced by land or sea against the enemies of Great-Britain ; shewing more plainly, the great advantage Britain has over other nations, by being masters at sea ; to which is added, an appendix, containing a scheme for manning the British navy, with less grievance to the subject; and a scheme to employ seamen ; of a copper mine near Hudson's Bay and of discovering the North-West passage, or determine there is no such passage ; with cautions and directions . ( HI )Retreats to bring the Wall ftrait at the Surface orFoot of the Rock. The next Thing to be done is to cut verticalDove-tail Grooves in the Rock, about a Foot deep,18 Inches broad at the Bottom, 16 at the Top orSurface of the Rock that is to be built againll, andabout 8 or I o Feet afunder •, in carrying up theWall fit long Stones into thefe Grooves (but not clofeto the Bottom of the Groove,) and let every fecondStone reach the Front of the Wall (when you can)and lye upon a Stretcher, till the Wall becomes toothick for one Stone to reach, then lay two or threeStones to reach the Front, taking Care to make ve-ry good Bond from the Dove-tails ; and if everythird Courfe is crampd together with Lead, it willgreatly add to the Security of the Work. ThefeDove-Tail Courfes cannot fail of holding the Wallfall to the Rock ; and if Care is taken to keep theRock very clean, and ufe good Mortar properlyagainft the Rock, and pour thin Mortar againilthe Dove-Tails, there cannot be any Doubt o
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Keywords: ., booksubjectmilitaryartandscience, booksubjectnavalartandscience
