CO129-204 - Acting Governor Marsh - 1882 [11-12] — Page 372

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14. Rubble Masonry. The Concrete base of the

dam, having been completed throughout, explained, and having been finished off in steps as shown in Drowing Nr 2 the erection of the rubble masonry structure upon the Concrete pedestal may now be proceeded with

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Before laying the first or forting course of masonry.

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floor of the substructure should be covered with u layer of rich cement mortur not less than two in chesthick on which the stones must be carefully bedded. The toe of the face of the wull, on both sides of the damn should be set buck five feet from the edge of the concrete, us, shewn in the Cowess section in Drawing N.3. The Ive of the Masonry will consist of a two foot course of ushlar headers and stretchers, upon which the random or uncoursed rubble work may be continued. Great must be taken that every stone is thoroughly beddect and that no cavities are left in the Mcwonry All spaces should be carefully packed with small stones, and the mortar should be unstinted in use. On both faces of the dam there should be at least one header to every yard and a hulf of face area of wall. These header may be two feet squire and may extend five feet inward from the face. The bond on the face of the wall, should be still father strengthened by a two foot course of ushlar, laid at intervals of every ten feet of vertical height of the dum . There will be about eight of these ashlar belting courses in the dam. The ashlar work,

meny five feet inward from the face of the wall. Masonry will finish in a two foot coping course of _ ashlars bedded in cement mortar. The side joints of the cope stones will have diagonal juggle holes cut down their full length, these must be rammed with pebbles and filled with liquid cement upon the completion of the Masonry.

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