Negretti & Zambra, London

 

A boxwood pocket sundial signed on the compass dial paper Negretti & Zambra, London.

Dials of this type are known as diptych dials. This dial dates from the second half of the 19th century.

Henry Negretti and Joseph Zambra became partners in 1850 and were one of the major makers of scientific instruments in the 19th and early 20th century.

The hinged boxwood instrument opens to reveal a compass and sundial in the base and a circular paper disc in the lid with a printed equation of time.

The lid is held open by a brass latch which keeps the string gnomen under tension. The sundial is graduated from 4 am to 8 pm in quarter hour intervals.

Note the makers name Negretti & Zambra London at the centre of the compass.

The compass is graduated in one degree intervals and has a 16 point compass rose to the centre. When the dial is closed a small pin operates a lever to stop the compass needle rotating.

The instrument measures 3” x 2¼” x ¾” when closed.

Stock No. C1112