Eppur Si Muove

When Shakespeare's First Folio went to print in 1623, only the seven classical planets were known. Sixteen years later, Giovanni Zupi was the first to prove conclusively that Mercury orbited the sun, by observing its orbital phases. Though Uranus wasn't identified as a planet until 1781, it was spotted in December 1690 by the first Astronomer Royal, John Flamsteed, who thought it was a star and duly catalogued it as 34 Tauri. Neptune had been spotted even earlier by Galileo, in 1612 when Shakespeare was writing Henry VIII with John Fletcher, but Galileo had also mistaken it for a star. The Sun and Moon were eventually demoted as planets, and the Earth promoted, giving eight known planets by the turn of the 20th century.

In 1930 the ninth planet, Pluto, was found by Clyde Tombaugh using a Zeiss model blink comparator. A blink comparator is a device which displays two images one after the other in quick succession so that you can easily spot if anything in the field of view has changed. Tombaugh had been looking at two plates of the region of sky around Delta Geminorum (also called Wasat) when he had noticed Pluto blinking at him.

During WWII, Shakespearean scholar Charlton Hinman, or Charlton Joseph Kadio Hinman to give him his full name, had been working for naval intelligence, analyzing "superimposed aerial photographs of enemy installations to see if they had been bombed or repaired." From this he got the idea to make a kind of blink comparator for collating works of literature, and came up with is now called the Hinman Collator. Dr. Ian Gadd has written a short summary of the machine.

The device allowed, for example, William J. Neidig to discover forgery in one of the 17th century quartos of the Merchant of Venice. The quarto stated that it was published by I. Roberts in 1600, but it matched exactly a title page from Pericles printed by William Jaggard for Thomas Pavier in 1619. Jaggard must've forged the copy and then backdated it. The Hinman Collator has also been used to detect other such forgeries.

According to research by Steven Escar Smith in Studies in Bibliography, Volume 53 (2000), by "1978, when the last machine was manufactured, around fifty-nine had been acquired by libraries, academic departments, research institutes, government agencies, a few private individuals, and a handful of pharmaceutical companies." Nowadays, Randall McLeod's Portable Collator or Carter Hailey's portable optical collator known as the "COMET" (yes, Hailey's COMET) are used for this kind of collation work, being cheaper and more portable.

Notwithstanding his categorisational mistake in identifying Uranus as 34 Tauri, John Flamsteed's Historia Coelestis Britannica listed about three thousand stars and gave their positions "much more accurately than any previous work".

Thanks to John Cowan for suggesting the topic and title, and for proofreading.

Cite: Palmer, S.B. (2005). "Eppur Si Muove", in: What Planet is This?
Archival URI: http://inamidst.com/notes/eppursimuove