Interior of blockmill at H M Dockyard, Portsmouth, c 1900.

View of block-making at the docks, Portsmouth. The development of the pulley block was fundamental to the workings of a ship as it meant heavier loads could be carried with less power. Increasing the number of pulleys increased the weight that could be moved. With the introduction of the Portsmouth block-making machinery in the early 19th century ship's pulley blocks no longer had to be made by hand. The machinery was designed by Marc Isambard Brunel (1769- 1849) and made by Henry Maudslay (1771-1831).