THE Ministry of Supply has recently announced that radium and radon can now be supplied for use in industrial radiography. Radium is available on hire only, and will remain the property of the Government. It can be hired for periods of not less than six months, and the average time to fulfil an order is two months. Radon is sold outright, and notice of one week is required for an order. Demonstrations of gamma-radiography for industrialists can be seen by appointment, at the Ministry's Armament Research Establishment, Woolwich, London, and at the National Physical Laboratory, Teddiftgton, Middlesex. Radium and radon are supplied by the Radio-chemical Centre, Amersham, Bucks, and applications for purchase or loan should be addressed to that establishment.