19TH CENTURY PORTABLE SUNDIAL

The earliest ones date back to 1556 and are kept in the Hermitage, they were designed to be worn around the neck and are a horizontal sundial with a sector gnomon to indicate the time.

A compass to orient the clock in the north-south direction and a plumb line on the gnomon to give the clock a horizontal position. All these elements are installed on the board, which can deviate from the horizontal position, making it possible to use the watch not on one, but in the range of latitudes: 47 - 57 degrees.