The Rack-and-Lever Butter Press: Cubes of a Set Weight

"This invention has for its object to afford a ready means of forming butter into lumps, regular in form and of certain specified weights, thus facilitating its sale and rendering it convenient to handle and pack for transportation". The follower is raised "through the agency of the gear-wheel and lever, the latter being carried upward until it passes the perpendicular, in which position, without the assistance of catches or similar devices, it will retain the standard and piston at a sufficient height above the box to allow the requisite quantity of butter to be placed therein". "A downward movement of the lever brings the follower into the box and into forcible contact with the butter in the box, which is caused to assume a compact cubical form thereby."

Make a square box with no top or bottom from hardwood, and a loose-fitting follower block to fit inside it. Screw the follower to the end of a dowel. Set up two uprights on a base board, joined by a cross-piece with a hole that guides the dowel straight up and down. Pivot a lever on one upright and pin its short end to the top of the dowel. This is a lever in place of Matthews' spur wheel and rack. A spur gear and rack do the same job with a longer stroke. Stand the box on wax paper on the base. Weigh the butter out roughly, put it in the box and bring the lever down hard. Lift the box, raise the follower and weigh the lump. Repeat and compare the weights, and compare the lump's side with the notebook.

**John Matthews** of Kirk's Mills, Lancaster County, Pennsylvania, filed US 147,511 on 2 January 1874; it is dated 17 February 1874. The box is held up by a catch-spring while the lump is taken out on its die. **Honest limits.** The force formula ignores friction in the guides and gear teeth, so the real squeeze is less. The pressure is an average over the box. The lever, wheel, box and density values are examples. Your weighed lumps are the measurement.