`A Compendium of All Knowledge'

Speculum meant only one thing to me – a rather unpleasant instrument wielded by a doctor, usually a gynecologist, to open a body cavity for examination. Once again, my indefatigable ignorance receives confirmation. On Saturday I came across the word in a decidedly ungynecological context – a field guide to the birds of the Pacific Northwest. It’s not a practicable book. The text is an odd amalgam of the impressionistic and the technically ornithological. The authors refer, without context, to a duck’s “speculum.” I went to the closest dictionary – the Webster’s Third I received as a gift more than 35 years ago – and found this as the fifth definition:

“a patch of color covering the distal portion of the secondaries of most ducks and some other birds (as domestic fowls), exposed in the closed wing, variously colored and often with bluish or greenish iridescence or a frame of a different color, and usu. most brilliant in the adult male.”

All my life I’ve marveled at avian iridescence without knowing it had a name, and certainly never guessing it shared a name with a doctor’s crow bar (a nice avian echo). The etymology seems straightforward – from the Latin speculum, meaning “mirror.” The Latin specere means “to look.” Speculum entered English during Shakespeare’s working life, c. 1597, but he seems not to have used it.

Webster’s first definition is the medical one I already knew. The second has two parts – an ancient mirror of bronze or silver; a reflector in an optical instrument, such as a telescope. Things started getting interesting with the third definition:

“a medieval treatise constituting a survey of life or of philosophy, history, and theology : a comprehensive, encyclopedic presentation of a aiming to be a compendium of all knowledge and usu. beginning with the Biblical account of creation, giving an outline of history, and thence passing chiefly to theology and scholastic philosophy…”

Putting Shakespeare aside momentarily, this definition alone proves the linguistic genius of English. The book I thought of immediately, though not medieval, is The Anatomy of Melancholy – “a compendium of all knowledge.” Number four is likewise unexpected:

“a drawing or table showing the relative positions of all the planets (as in an astrological nativity…”

That a Latin-derived word just over 400 years old can mutate so variously makes one proud to have inherited so fecund a language. Of course, there’s more: Ophrys speculum is a species of orchid. Speculum is the name of “a San Diego California grindcore/death metal band,” and of the scholarly journal of the Medieval Academy of America. A speculum metal is “an alloy containing copper and tin used for making all-metal mirrors.” Roger Bacon wrote Speculum Alchimiae; John Gower, Speculum Meditantis. Getting back to the avian sense, Darwin used it simply in The Descent of Man:

“The wild-duck offers an analogous case, for beautiful green speculum on the wings is common to both sexes...”