Letter from Samuel F. B. Morse to his brother Sidney, 31 May 1844
Seven days after his great success with the first telegraph message, Morse writes, in a humble and circumspect tone, to his brother, Sidney, of the responsibilities of success. Twice he quotes the famous message, "What hath God wrought," and uses it to invoke his deep religious feelings. Still feeling the flush of success, he quotes a former opponent, now won over, as saying, "It is an astonishing invention."
The Papers of Samuel Finley Breese Morse
Manuscript Division