Experiments have two great uses - a use in discovery and verification, and a use in tuition. They were long ago defined as the investigator's language addressed to Nature, to which she sends intelligible replies. These replies, however, usually reach the questioner in whispers too feeble for the public ear.
Six Lectures on Light Delivered in America in 1872-1873 (3rd edition), Lecture I (p. 3), D. Appleton & Co. 1901