May 24, 1844

What hath God wrought

Morse sends “What hath God wrought” over the Washington–Baltimore telegraph line

The four famous words were chosen by Annie Ellsworth, not composed by Morse — and Baltimore sent them straight back.

24 May 1844: Capitol to Baltimore

On 24 May 1844, Samuel F. B. Morse transmitted "What hath God wrought?" from the U.S. Capitol in Washington to Alfred Vail at a Baltimore & Ohio Railroad depot in Baltimore. It formally opened the experimental line Congress had financed with $30,000.

Annie G. Ellsworth, daughter of patent commissioner Henry L. Ellsworth, had selected the wording from Numbers 23:23. The surviving outgoing tape credits her suggestion and carries Morse's handwritten authentication.

The demonstration was a round trip

Vail received the message and immediately transmitted the same words back to Washington, demonstrating two-way operation of the completed line.

Institutional accounts measure that line at 38 or 40 miles. The Library of Congress holds the outgoing 24 May tape; a similar Smithsonian strip is a Baltimore-to-Washington souvenir made on 25 May.

Not the first electrical telegram

Cooke and Wheatstone had demonstrated a practical electric telegraph in Britain in 1837, and Morse, Vail and their collaborators had shown versions of their own apparatus before 1844.

The defensible description of 24 May is narrower: the first formal public message over Morse's completed Washington–Baltimore line.

Where in the Capitol he sent it from is less certain than what he sent. The Library of Congress identifies the room as the former Supreme Court chamber; the Senate Historical Office notes that identification rests on accounts written decades later.

Sources

Researched 23 Aug 2026 6 sources 2 audit passes

How this was checked

Researched from the web into a fact sheet, rewritten from that sheet, then audited against it by a different model. How the pipeline works →

What the sources leave uncertain

The date, participants and message are firmly documented.
The Library of Congress identifies the Capitol room as the former Supreme Court chamber, but the Senate Historical Office notes that this precise room identification comes from accounts written decades later.
Institutional sources variously call the Baltimore endpoint Mount Clare depot, the B&O railroad depot or Pratt Street Station. The terminology reflects uncertain or changing depot names rather than uncertainty about Baltimore as the destination.