In his laboratory in the cupola of Bedlam, Hooke had used Comstock gunpowder to drive the piston of such an engine, and had shown it could do work—or in Hooke-language, that it could give service as an artificial muscle. That was because Hooke the cripple had wanted to fly, and knew that neither his muscles nor anyone else’s were strong enough. Hooke knew that there were certain vapors, issuing e.g. from mines, that would burn with great violence, and hoped to learn the art of generating them and of conducting them into a cylinder to drive a piston—which would be an improvement on the gunpowder. But Hooke had other concerns to distract him, and Daniel had distractions of his own that led him apart from Hooke, and if Hooke’s artificial muscles had ever been perfected, Daniel had never seen them, nor heard about them. Now Newcomen was finally doing it; but his machines were great brutish contraptions, reflecting the fact that Newcomen was a blacksmith to miners where Hooke had been a watchmaker to Kings.