MIDDLE TEMPLE LIBRARY / SCIENCE PHOTO LIBRARY MIDDLE TEMPLE LIBRARY / SCIENCE PHOTO LIBRARY
Block house and blocks, 19th-century artwork. Block houses are a small, isolated type of fortification. The blocks at bottom are designs used for block-and-tackle lifting systems. These are systems of ropes and pulleys, with the rope threaded between the pulleys. The design of a block-and-tackle system enables the lifting of heavy loads. For just the blocks, see C021/7825. Artwork from 'Encyclopaedia Metropolitana' (1845).
Model release not required. Property release not required.