This sturdy industrial building housed a sawmill for cutting and shaping ship timbers and planks and a joiner shop for the finer woodworking that went into vessels' cabins, deckhouses, railings, and interiors. In 1909, the shed addition on the north side provided more lumber storage and a place for the schooners' small boats to be built. The mill's lumber ramp and interior can be seen under the bowsprit of the 4-masted schooner Florence M. Penley, launched in 1903.