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Inventory no. 40698 - Former Display Label


Silvered brass; with original leather-covered and leather-lined wooden box, tooled in gold. Signed, "Fecit Iohan Engelbrecht Beraunensis. 1792".

This instrument may be used in any latitude between 40° & 60°, by tilting it until the point of the plummet lies against the appropriate division of the latitude-scale engraved at the base of the gnomon.

The hour-plate is engraved with hour-lines for equal hours, Babylonian and Italian hours. Also engraved are lines indicating the declination of the sun throughout the year. At any particular time the declination is indicated by the shadow cast by the notch (marked 'a') in the sloping edge of the gnomon; conversely, if the date, or the declination of the sun, be known, the shadow of the notch may be used to orientate the dial on the meridian.

[G 142]
Lewis Evans Collection.

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