What is (a) A kind of tenon on the end of a joist, received into a notch in a bearing timber, and resting flush with its upper surface. (b) A tenon in a scarf joint; a coak. Knight called?

cog — (Carp.) (a) A kind of tenon on the end of a joist, received into a notch in a bearing timber, and resting flush with its upper surface. (b) A tenon in a scarf joint; a coak. Knight. (Webster's 1913.)

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