To Set Fire To A Combustible Body By Reflection

Place two concave mirrors at about twelve feet distance from each

other, and let the axis of each be in the same line. In the focus of

one of them place a live coal, and in the focus of the other some

gunpowder. With a pair of strong bellows keep blowing the coal, and

notwithstanding the distance between them, the powder will presently

take fire.

The mirror may be either made of glass, metal, or pasteboard gilt.

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