Signatory: The letter is signed by G. B. Airy, a prominent mathematician and the 7th Astronomer Royal, known for establishing the prime meridian at Greenwich. • Date & Origin: Dated April 15, 1850, from the Royal Observatory, Greenwich. 1850 was a significant year for Airy, as it was the year he designed the Airy Transit Circle telescope. • Recipient: Addressed to Robert Cole, Esq., who appears to be the prominent 19th-century scientific instrument maker or a related collector. • Content: Airy is acknowledging receipt of a portrait of Henry Andrews (an astronomer and mathematician), which adds minor historical interest to the piece. This is letter is from my own collection of History of Astronomy.
