The science of weighing played a considerable part in the ancient Egyptian's life, not merely in everyday trade but also in the religious ceremonies to which they were deeply committed. The balances employed were originally of simple patterns and existed before 3200 B.C. They had two copper and silver pans suspended by cords at the ends of the centrally supported horizontal beam. Their use was chiefly restricted to the weighing of metal.
By Egyptian belief, when a died his heart had to weighed in the presence of Osiris, the great god of the dead. The man's soul was assumed to be represented by his heart, the weight of which must exactly balance that of a feather - the symbol of righteousness; if it did so, the soul of the deceased was taken into the company of the gods. For ordinary people, this weighing must have left heaven rather empty. Many hieroglyphics show this ceremony, together with detailed drawings of the balances employed.
Egyptian weights were originally of hard stone, carefully polished and marked; but in quite remote times cast bronze weights were also in use. A beautiful set, designed in animal forms, together with the actual balance, was buried at Amarna (c. 1450 B.C.) (Fig. 4).
Other copper weights made in Crete had the shape of little axes, each inscribed with the appropriate number of minae. The London Science Museum possesses a fine set of ancient lion bronze weights from Assyria, marked with the names of kings. These weights were cast and, if over-size, were reduced to their correct values by chiselling pieces from the base; if on the other hand they were light, the hollow body of the lion was partly filled with lead.The ancient Chinese also used cast bronze animal weights.