Francis Hauksbee's air pump Finish:Float frame with the tree of True

with the tree of True Liberty

Lord Mayor 1824

With a facsimile signature lower right

Hot weather at London's Hyde Park Lido

Francis Hauksbee's air pump Finish:Float frame with the tree of TruePlate illustrates pp. 17 18, 'The Description of the Machine for giving a swift Motion to Bodies in Vacuo, without admitting the External Air', and shows Hauksbee's air pump connected to a wheel mechanism which imparts a rapid rotation speed to a spindle within the glass dome of the air pump. Plate II from Physico mechanical experiments on various subjects, by Francis Hauksbee (London, 1709), presented to the Royal Society by the author on 26 October