"Having one day read that Paschal invented a certain arithmetical machine, by a mere effort of his own genius, he could take no rest till he invented one of the same description. He likewise constructed with his own hand a mercurial watch or pendulum, which kept going 27 minutes, and served to ascertain precise portions of time in his physical experiments. His arithmetical scales and a machine for facilitating the art of drawing in perspective are no less worthy of our notice."