Based on self-drying linseed oil. Firstly, a rich sealer is rubbed in and after being left to dry for approximately 24 hours a fatless, easy-drying preserver is applied and left to dry properly or, as may apply, rubbed down. If the sealer and preserver are cut with cheap mineral oils, drying take a very long time. The objective is open-pore, aesthetically perfect surfaces that may however become rough due to subsequent relatively high air humidity. This process was replaced in the 60s by the better 'Scandinavian Surface Treatment'