He had a considerable impediment in his speech, a defect which is in general painful to others; but the doctor repaid his auditors so well for making them wait for his wit or his knowledge, that he seldom found them impatient.' At Lichfield he met Mr.Bolton of Snow Hill, Birmingham, who asked him to his house, and showed him over the principal manufactories of Birmingham, where he further improved his knowledge of practical mechanics.

His time was now principally devoted to inventions; he received a silver medal in 1768 from the Society of Arts for a perambulator, as he calls it, an instrument for measuring land.

This is a curious instance of the changed use of a word, as we now associate perambulators with babies.

In 1769 he received the Society's gold medal for various machines, and about this time produced what might have been the forerunner of the bicycle, 'a huge hollow wheel made very light, withinside of which, in a barrel of six feet diameter, a man should walk.

Whilst he stepped thirty inches, the circumference of the large wheel, or rather wheels, would revolve five feet on the ground; and as the machine was to roll on planks, and on a plane somewhat inclined, when once the vis inertia of the machine should be overcome, it would carry on the man within it as fast as he could possibly walk.