Letters

‘Black hole’ origins
“Black hole theory and discovery” (Back Story, SN: 7/4/09, p. 6) credits John Archibald Wheeler for inventing the term black hole in 1967. This is a very widespread choice, but it cannot be right. In January 1964, your ancestral publication, Science News Letter, carried a short article titled “‘Black holes’ in space,” which reported on a session at the AAAS meeting in Cleveland. Hong-Yee Chiu, who organized and chaired that session, remembers hearing the phrase from the late Robert Dicke in about 1960–61.
Virginia Trimble, Irvine, Calif.

Trimble, an astronomer at the University of California, Irvine, is correct, and we are gratified to be credited with the first use in print of “black hole” as an astrophysical object (see the original story on the Science News website at http://bit.ly/1dkgEg). But apparently Wheeler, who popularized that name, did not learn of it from Science News Letter. By his account, it was suggested by an unknown questioner in the audience during a 1967 lecture given by Wheeler, who then used it in a later lecture that was published in the Spring 1968 issue of American Scientist. — Tom Siegfried

Bog iron
It is unfortunate that “The iron record of Earth’s oxygen” (SN: 6/20/09, p. 24) didn’t at least mention bog iron, which was the major source of iron ore during the Iron Age, at least in the Northern Hemisphere. I understand that it was, and is still, found in bogs left behind after the last ice age. It sounds like the same mechanism of formation.
John O. Kopf, Cupertino, Calif.

The chemistry is similar, but banded iron formations arose when dissolved iron and dissolved oxygen reacted underwater. Bog iron forms when iron-rich waters seeping from a bog are exposed to oxygenated air. — Sid Perkins

Squished skull
The skull photo with “Ancient Andean civilization likely spurred by maize” (SN: 8/1/09, p. 16) looked odd. Did the Wari have different shaped heads than other modern humans?
Henry Jones, Baton Rouge, La.

No. Inhabitants of the ancient site studied by archaeologist Brian Finucane took skulls such as the one shown from enemies killed during raids and modified them with various tools, giving them an odd shape — a fact that should have been mentioned in the caption. —Eva Emerson