§ Mr. Canavanasked the Secretary of State for Scotland whether he will name the fluorides which he is considering permitting authorities in Scotland to put in public water supplies.
§ Mr. John MacKayI cannot anticipate what the proposed legislation on fluoridation of public water supplies might contain about fluorides. I understand that the compounds used previously in Scotland and in use in England and Wales are hexafluorosilicic acid H2 Si F6 and sodium hexafluorosilicate Na2 Si F6.