Possible Clues:

• Methods or rules for successful procedures
• Four male cooks creating recipes
• Chemical "recipes"
• Tried and tested methods to get a chimney up in front
• Maths relationships
• Mathematical relationships or rules stated in symbols
• Make urgent list as explained initially of sets of chemical symbols
• In favour of withdrawing alum from key prescriptions
• Mathematical rules expressed in algebraic symbols
• Sets of chemical symbols, make universal list as explained initially