A lode.

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1812.  Leads (or loads) are the smaller fissures that connect with the larger, which are called by the miners caves.—Brackenridge, ‘Views of Louisiana’ (1814), 148. (N.E.D.)

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1817.  Although the district of country which contains the present diggings, is considered as comprising the mines, I am of opinion that the lead extends to a very great distance beyond those limits.—John Bradbury, ‘Travels,’ p. 254.

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