For the marking liquid-rub together in a small mortar five scruples of lunar caustic with one drachm of gum arabic, one scruple of sap-green and one ounce of rain water. Keep the bottle three days in the sun.

For wetting the linen - mix together a quarter of an ounce of salt of soda, a heaped table-spoonful of powdered gum arabic, and two ounces of hot water.