Typical set of mining instruments housed in a box with lid. The following items are fitted into special compartments: a mining theodolite consisting of a graduated horizontal disk with two small magnetic compasses, and a graduated circle inserted on a vertical rod and fitted with a hook-shaped index; a triangular clinometer; a protractor disk with an index; another disk fitted with a mobile quadrant at its center to compute slopes in mineshaft excavation; and two plummets. Brought to Florence from Germany by Prince Mattias de' Medici in the first half of the seventeenth century.