Engraving showing the completed lighthouse being provisioned, (left), and the entrance to the lighthouse as well as the five internal rooms of the house (right). Note the drop hole which runs down through the centre of the solid courses. This allows the machinery weights to descend. Illustration from 'An account of the Bell Rock Light-house: including the details of the erection and peculiar structure of that edifice; to which is prefixed a historical view of the institution and progress of the Northern Light-houses' by the designer of the Bell Rock Lighthouse Robert Stevenson (1772-1850), published in Edinburgh in 1824.
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