Samuel Morse sends the message "What hath God wrought" (a biblical quotation, Numbers 23:23) from the Old Supreme Court Chamber in the United States Capitol to his assistant, Alfred Vail, in Baltimore, Maryland, to inaugurate a commercial telegraph line between Baltimore and Washington D.C.

The Old Supreme Court Chamber is the room on the ground floor of the North Wing of the United States Capitol. From 1800 to 1806, the room was the lower half of the first United States Senate chamber, and from 1810 to 1860, the courtroom for the Supreme Court of the United States.

Samuel Finley Breese Morse (April 27, 1791 – April 2, 1872) was an American inventor and painter. After having established his reputation as a portrait painter, in his middle age Morse contributed to the invention of a single-wire telegraph system based on European telegraphs. He was a co-developer of Morse code and helped to develop the commercial use of telegraphy.