Beauty Spots for Venus

Martin responded to the transits with books, engraved prints and lectures. As an instrument maker, he even found an opportunity for a novel telescope accessory.
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The telescope here is an example of the small reflectors which Martin sold under the (unsuccessful) name “megalascope”. The engraving in his Young Gentleman and Lady’s Philosophy shows it fitted with an attachment for projecting a transit image of the Sun. Here it is being used as a demonstration device: the small dark circles representing Venus are actually produced by four beauty spots mounted on a slide.
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