Note 202 — Chapter XV · Watt again visits Cornwall—Invention of the Rotary Motion—The Patent Right again assailed.

In June, 1780, we find Boulton describing to Colonel Watson the progress of the Soho business, as follows:—“Since I had the honour of seeing you in England we have erected upwards of 40 of our new steam-engines, and have (from so much experience) obviated every difficulty, and made it a most practicable and perfect machine. The steam wheel we have not meddled with since you were at Soho, as we have been fully employed upon large beam-engines; besides, we have applied the beam engine to rotative motions so successfully that the wheel engine seems almost unnecessary.”