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Inventory no. 55460 - Former Display Label


Ivory; brass plummet. Signed 'Cco. L. FRISI. F. 1794'.

Inscribed, 'Quadrante Verticale Per Gr. 45:28'.

In use, the plumb-line is held taut against the appropriate scale of months and the small red bead on the plumb-line adjusted to the date. The plumb-line is then allowed to hang freely, and the sights are directed towards the sun. The bead will then indicate the time in Italian hours.

The plummet is a skirret equipped with a pin, so that, when not in use, it may be plugged into a hole at the top of the quadrant, with the plumb-line wound round it. There is a small ivory plug to prevent the sights from becoming clogged.

A scale of degrees is marked on the right-hand and lower edges of the quadrant.

[I. 20]
Lewis Evans Collection

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