§ Dr. Strossasked the Parliamentary Secretary to the Ministry of Works, as representing the Lord President of the Council, when measurements were first commenced in London on the radioactive content of the atmosphere for how long such measurements have been taken by the Physics Department of the Marsden Hospital; and how the technique used there compares with or varies from that used by the Medical Research Council.
§ Mr. BevinsNo measurements of atmospheric radioactivity in London earlier than 1947 are known. Since that date, measurements of radiation backgrounds have been made in the Physics Department of the Royal Marsden Hospital; these are the measurements made114W under the auspices of the Medical Research Council. Other measurements made in the Physics Department since 1930 were designed to ascertain the degree of exposure of workers using X-ray apparatus and radium.