This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
10 lb. whiting and 1 lb. white-lead, mixed with the necessary quantity of boiled linseed oil, adding to it 1/2 gill best salad oil. The last prevents the white-lead from hardening, and preserves the putty in a state sufficiently soft to adhere at all times, and not get hard and crack off, suffering the wet to enter, as is often the case with ordinary hard putty.