Brick chimney The overall height of the stack is , including a brick chimney tall and the downhill side of a concrete foundation high. This was the height when new in 1918, but loss of the terra cotta that covered the top course of bricks since then reduced its height one or more inches. The lowest of the brick chimney is an
octagon, the
vertices of which point to the
cardinal and intercardinal directions, north, northeast, east, etc., while its sides face the secondary-intercardinal directions, north-northeast, east-northeast, etc. Two large vertical openings are in the octagonal portion, each , on its east-southeast and south-southwest sides. When operational, the main flue carried hot exhaust gases to these openings and then into the stack from the smelter which was on the north side of the hill upon which the stack rests. The base of the octagon was side to side across its bottom before the loss of its terra cotta covering. But the inner surface of the octagon is circular with an inside diameter of across its bottom. The wall thickness of the octagon at its bottom ranges from at the center of a side to at each vertex. The rest of the chimney is a slightly tapering cylinder with a top inside diameter of and a wall thickness of just below a slightly flared top.{{efn-ua Most are radial bricks that are curved to match a
sector of a cylindrical wall. The brick chimney weighs .
Concrete foundation The lowest part of the stack is a concrete foundation or
footing that is built on sloped ground with a grade of because it is just below the top of a hill. It is high above ground at its downhill side and high above ground at its uphill side. It is a hollow octagon, side to side on top and side to side across its bottom, high on its downhill side and high on its uphill side, a third of the foundation being below ground. The stepped bottom of the foundation fits the stepped rock formation upon which it rests. The floor of the stack is generally conical leading down below the brick chimney to a rectangular grate, then into a square horizontal duct that exits the stack at the center of the downhill side of the foundation on its south-southeast side. This allowed any valuable metal dust particles left in the flue gases that precipitated down to that conical floor to be collected by a car on a track within the duct and sent back to the smelter for more processing. ==Construction==