A scanning machine for presenting pictorially and quantitatively the distribution of radioisotopes in vivo 'A scanning machine for presenting pictorially and quantitatively the distribution of radioisotopes in vivo' was written by J.R. Mallard and C.J. Peachey, Department of Physics, Hammersmith Hospital. This article was a contribution presented at the Third International Conference on Medical Electronics on July 27, 1960. This article is contained within a reprint from the Proceedings of the Third International Conference on Medical Electronics along with "Radioactive arsenic 72 for brain-tumour scanning", also written by J.R. Mallard, ref MS 3819/1/18. 1960