IN recent chemical tests carried out on the Piltdown skull, the accurate determination of fluorine was of decisive importance. It may therefore be of interest to mention that the discovery of fluorine in the human skeleton has been attributed1 to Arthur Connell, first professor of chemistry in the University of St. Andrews (1840–;62). Further, to quote from a publication of 1864, “as an example of his nicety as an analyst we may refer to his determination of the constituents of Greenockite from a single grain of that mineral”2.