| Description | Letters from Matthew Wasbrough, from 1778 and 1779. Wasbrough, a Bristol brass founder and clock-maker, invented a rotative mtoion for engines based on a pawl and ratchet motion. He had protracted negotiations with Boulton & Watt about using his motion on their engines. Boulton & Watt also ordered copper eduction pipes for some of their Cornish engines from him. |