"I am but a weak instrument in the hands of God."

"I have always endeavored to be a faithful interpreter of nature, and not a presumptuous dictator."

"I have often observed that those who are most unwilling to acknowledge their errors, are generally the most in the wrong."

"I have always been of the opinion, that the best way to discover new truths, is to be constantly trying new experiments."

"The air is not an empty space, but a real and ponderous body."