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Inventory no. 37626 - Former Display Label

French HORIZONTAL CANNON DIAL
c. 1900

Brass, silvered brass, etc. Unsigned and undated. Diameter of case 54 mm.

The hour-lines of the dial are marked for latitudes between 45° and 52°; the gnomon is adjustable for any latitude within that range.

As well as a magnetic compass and two levels for correctly setting the dial, this instrument includes a burning-glass and a model cannon. The burning-glass can be adjusted to the sun's declination so that, at noon, it focuses the sun's rays on the touch-hole of the cannon, thereby firing a small charge.

[M. 4]

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