The Centre Lid Lifter: A Knob in a Hollow, a Fork From Any Side

"The object of my invention is to provide a stove-lid and lifter which are so constructed that the lifter can be applied to the lid from any position and in any desired direction, which is not the case with the ordinary stove-lid and lifter, and which is applied to the lid at its center, so that it is easier to lift than where it is applied to the lid at the side, as usual." The lid has at its center "the cavity B", and "extending upward from its center is a headed projection C, which forms a knob". "The lifter D has its lower end bifurcated to form a fork", and a rib across its underside forms "a stop, bearing, or fulcrum for the lifter when it is placed in the cavity, by engaging the upper face of the lid". "It also enables the lid to be lifted off the stove by hand when the stove is cold by catching hold of the headed projection with the fingers, as when building a fire, and a lifter cannot be at that moment found."

Take a saucepan lid with a centre knob, cold. Hook the force meter under the knob and lift: note the reading and that the lid hangs level. Now hook it under the rim and lift: note the reading and measure how far the lid tilts with the protractor. Then hold a steel ruler level by one end and hang the lid from it, first 5 cm and then 15 cm from your hand: feel the twist in your wrist grow with the distance. Compare with the notebook's moment, weight times distance.

**Edmund Kuhn** of New Albany, Floyd County, Indiana, filed US 465,865 on 8 June 1891; it is dated 29 December 1891. **Honest limits.** The moment is a simple static estimate: the lid treated as a flat disk with its weight at its centre, lifted slowly. Masses and radii are examples. Your force and tilt readings are the measurement.