The Old Man of Hoy is Britain's tallest sea stack, standing 137 metres high and approximately 30 metres wide at its base. It has been carved out of the main headland rock by the sea exposing many layers of red sandstone. The stack used to be joined to the main headland by an arch, though this gave way in a severe storm to leave just the pillar. From a collection of 57 albumen photographs of rock and glacial formations in the United Kingdom, Europe, North America and Asia.
© Science Museum / Science & Society Picture Library