The invention of balance scale

People have always needed to compare weights of animals, grain, money etc. They invented a balance scale on which two pans were suspended, one from each end of a balance horizontal bar. They then put something of known weight on one pan and the unknown on the other pan.

The word balance comes from the Latin “bi lanx” that means double pan. The balance scale essentially consists in a couple of pans suspended from a yoke; the latter is suspended in the middle point between the points in which the dishes are suspended.

The fulcrum or the middle point is where the equilibrium occurs. A teeter-totter is an example of a balance scale. Metal scales dating to 5000 BC have been found in archeological digs.

Balance scales were in use by 4000 BC in both Egypt and China. The ancient Egyptians are thought to have developed the first known weighing instruments, which they probably used to measure gold. They were able to accurately measure to a small fraction of an ounce by 1500 BC.
The invention of balance scale