Note 219 — Chapter XV · Watt again visits Cornwall—Invention of the Rotary Motion—The Patent Right again assailed.

“Yesterday I went to Penryn and swore that I had invented ‘certain new methods of applying the vibrating or reciprocating motion of steam or fire engines to produce a continued rotation or circular motion round an axis or centre, and thereby to give motion to the wheels of mills or other machines,’ which affidavit and petition I transmit to Mr. Hadley by this post with directions to get it passed with all due expedition.”—Watt to Boulton, 26th July, 1781.