The Bodleian Library saw a reunion of inventor and invention on September 2 when Professor Randall McLeod from the University of Toronto conducted a masterclass in the use of the visual collator he invented and built. The device is used to compare copies of printed books. Even copies of the same edition of a book printed in the hand-press period might differ from one another, as corrections were made during a press run.
The Bodleian has owned a McLeod collator since the 1980s. It was kept first in the Modern Papers Reading Room (Room 132 in the New Library) and later in Duke Humfrey’s Library. The library’s copy of the guide to its use, (PDF linked below) has been headed in pencil: “Please do not remove from Room 132”.
The collator itself was returned briefly to Room 132 for a special visit by Professor McLeod, who talked about his invention and demonstrated its use to a class of 25 visitors.
Bibliographers and book historians collate printed texts, comparing copies of the same edition, in order to detect any of the differences that may arise due to stop-press corrections, accidents in the press, or later annotations. A famous example of this process was the work done in the 1950s by Charlton Hinman on the First Folio of Shakespeare’s plays, resulting in Hinman’s study, The Printing and Proof-Reading of the First Folio of Shakespeare (1963), that highlighted the many differences in the finished products that might leave an early-modern printer’s shop under the same title. By the same token, as masterclass participant Ian Gadd of Bath Spa University commented, collation can reveal sections of text that match so exactly — including errors — that the publisher’s claim of an updated edition might conceal the fact that only some of the type had actually been re-set.
Collation may be done by hand, but this is a laborious process of checking every character. As with proofreading a word-processed document, the brain may falsely supply what the eye does not see. Scholars have sought ways to make the process of comparison entirely visual, so that the differences on a page leap out to the eye, and they have looked for ways of superimposing images of two supposedly identical pages.
Hinman’s own answer to the question, for the daunting task of collating the massive First Folio, was the Hinman Collator. This machine adopted the principle of the blink comparator, a device used by astronomers, to make tiny differences in the images jump out as first one, then the other, page image flashed in front of the operator’s eyes.
The Bodleian Library bought a Hinman Collator in 1970. At first this was kept in Room 132 of the New Library, which was then the Bibliography Room (housing the library’s handpresses) until that room became the Modern Papers Reading Room. Then the collator’s blinking lights were seen to disturb readers, and it was retired to the library stack. It is now unfortunately not functional.
Professor Randall McLeod used his own invention to collate copies of John Harington’s translation of Ariosto’s Orlando Furioso. This device works on a different principle from the Hinman, as it uses the operator’s two eyes viewing texts simultaneously.The two images are then superimposed by the human brain, trained for binocular vision. In McLeod’s words, the images ‘suddenly fuse [and] [t]he brain … sees only one page’. Where the two settings of type are identical, the image appears solid, but any differences appear to ‘shimmer,’ and gain depth, like the pictures seen through a stereoscope.
During the class Professor McLeod compared copies of the 1621 edition of Samuel Rowley’s play, When you see me you know me, revealing several variants.
Other McLeod collators are owned by Cambridge and the University of London; the National Library of Wales; Università di Udine; New York Public Library, and the Pierpont Morgan Library.
A guide to the use of the McLeod Collator can be found here:
McLeod_Collator_Guide
Also see an article from Lingua Franca, 1997, by Daniel Zalewski.
At the 
