Radiocarbon comes of age at Oxford

The Radiocarbon Accelerator Laboratory at Oxford is described. The method of accelerator dating with a high-energy mass spectrometer which counts carbon-14 atoms in the sample is contrasted with conventional techniques in sensitivity and time needed for each determination. The problem of avoiding contamination of the sample, particularly by modern carbon is discussed. An account is given of the calibration of radiocarbon dates. Possible future developments e.g. by counting beryllium-10, are mentioned. (U.K.)