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The last should be made from 3-inch deals, cut acrossinto battens 1" x 3", and a certain quantity into poles3 inches square for uprights.
Thus provided, the works should be traced out, asexplained in Article * Battery/ with the Hambro’ line •stretched upon that corresponding with the entire crestof the parapet (o) in the annexed diagram; and from thisthe dimensions marked out by pickets firmly driven intothe ground, transferring the works from the plan ap-proved ; when probably some modification will be foundnecessary, when the tracing is completed, by markingit on the ground with a sharp spade, called spit-locking.
b. Profile. —The question of relief having been de-cided upon in reference to command, or defilade, oras a security against artillery, or only against musketry,the dimensions will be found in figs. 45 to 53 : thepoles must be driven into the ground, correspondingwith the angles of the work, and the battens nailedto them, as explained in the diagram.
The under surface of the battens give the dimen-sions of the work, by which means the uprights onlywill be lost, and buried in the ground. And in orderto judge whether the interior of the work is sufficientlycovered from without, or defiladed, if in the vicinity ofhigh ground, a cord should be stretched from profileto profile, o to o, (see the diagram, corresponding withthe crest of the parapet.)
c. Construction and Execution of Field-Works. —Theremblai and dtblai having been calculated from one ofthe profiles chosen in the figures of the Plates on Field Fortification , the materials taken from the ditch shouldbe so placed that the work may be raised to the wholebreadth of the parapet and banquette and of rampart,and should be carried up in even courses of about 18inches or 2 feet, and well consolidated with the earthenrammers to the level of the banquette, when arrange-ments must be made for revetting the parapet.
d. Revetments of Field-Works. —These are generallynecessary to the interior slope of the parapet, and some-times to the exterior, to give the necessary solidity, andprevent it crumbling away by the effects of the weather,otherwise the parapets would lose their proper dimen-sions. The interior slopes may be lined with fascines,gabions, or hurdles, as likewise the cheeks of theembrasures, but artillery in these works are generallyen barbette , or as is explained in Article ‘ Battery/Section xm. There are resources to be found onthe spot occasionally, such as sods, also old buildingstones and bricks: the latter could be built up within2 feet of the crest of the parapet, and then completedwith sand-bags or sods, or earth well beaten. Sun-
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