"I wanted to create a mechanical lift device for arborists to ensure a fallen tree lands precisely where needed," said an inventor, from Henderson, Ky., "so I invented the MECHANICAL WEDGE. My design ...
Discover how manure, wood ash, and modern NPK fertilizer transformed American agriculture long before tractors and steam engines.
An underwater ship -- A siphon for raising water -- Lifting weights by water, and a portable siphon -- Construction of sluices to raise ships to any height -- A machine worked by fire which can throw ...
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