Convert Your Common Physical Balance into a Microbalance

The common physical balance consists of a beam supported at the center by a knife edge made of steel or agate. This knife edge rests on a plate of hard material fixed to the top of the pillar. At the two ends of the beam and at equal distances from the central knife edge, there are two knife edges pointing upward. From these are hung two stirrups that carry scale pans of equal masses. A pointer is attached to the middle of the beam perpendicular to it and this moves over an ivory scale fixed at the bottom of the pillar. This is the simple description of the common physical balance. By fixing a reflector and mirror, this can be converted into a very sensible balance and can even be used as a microbalance.