"I have always been of the opinion, that the best way to discover the secrets of nature, is to interrogate her by experiments."

"The Lord is pleased to teach me by my failures."

"I am not ashamed to confess that I have learned more from observation than from all the books I have ever read."

"I have seen a dog, whose hind legs were cut off, and yet it lived for a considerable time."

"I have observed that mercury, when heated, will rise in a tube against its natural tendency."