The article by Joseph Reader and Charles Clark, “1932, a watershed year in nuclear physics” (Physics Today, March 2013, page 44), was most interesting and warrants a few comments.
On page 46, the authors put “the Cavendish Laboratory in Oxford.” The Cavendish, first known as the Devonshire Laboratory, is at Cambridge University. It was established in 1874 by William Cavendish, the seventh duke of Devonshire, who donated the funds for it and served as university chancellor. His relative, Henry Cavendish, was a chemist and physicist who first “weighed the earth.” The lab’s first professor was James Clerk Maxwell, who renamed the facility to commemorate the contributions of both Cavendishes.
Reader and Clark also mention Ernest Rutherford’s frugality, which is best understood in the context of his modest background as the son of a farmer. A second reason for his fiscal restraint is that research funding was not plentiful in the time between the two world wars, and the Depression did not help. Rutherford’s frugality is corroborated by a quote related to me by one of my professors at Birmingham University in the UK, Philip Moon, a student of Rutherford’s in 1928–31, who quoted him as saying, “We have no money, so we have to think.” More important, Rutherford was known for doing and encouraging innovative work with simple experiments. Also, as Moon related it, Rutherford encouraged independent thought, even at the expense of precious resources. Moon told us about how someone had complained to Rutherford that a certain investigator spent laboratory resources on useless research. Rutherford responded, “Let him find out for himself, and he will not do it again.”
The authors’ mention of John Cockcroft and Ernest Walton brings back memories of one member in their group, another of Rutherford’s students: William Burcham, who was head of the physics department when I entered Birmingham University. He had been intimately involved in the upgrade of the Cockcroft–Walton apparatus to 2 MV. The upgrade was made possible through a gift of £4000 from Herbert Austin, the automobile manufacturer.1
I also offer a brief comment on positron emission tomography (PET) imaging. Although carbon-11 is indeed used for some medical imaging applications—prostate cancer detection, for example—its relatively short half-life of around 20 minutes requires a cyclotron on hospital grounds to produce it. The $2 million expense of setting up a medical cyclotron for isotope production impedes the widespread use of 11C. The more preferred and widely used isotope for PET imaging is fluorine-18; its half-life of around 110 minutes makes it more practical to use. Furthermore, 18F-labeled fluorodeoxyglucose, a glucose analogue, provides a wide range of medical applications.
Some of us can still relate to Rutherford’s era through the privilege of having been taught by his students.
