"I once kept a viper in a sealed glass jar until it died, to observe the effects of air deprivation."

"I have always looked upon the study of nature as a means of enlarging the human mind."

"I have often wished that I had lived in an age when philosophy was more free and less tied to the authority of the ancients."

"It is a shameful thing for a Christian to be ignorant of the works of nature."

"I value not so much the multitude of experiments, as the exactness and fruitfulness of them."