Red oxide for painting on outside brick walls should be mixed with raw linseed oil and a little patent driers; see that the walls are thoroughly dry before painting them. Boiled linseed oil should uot be used, as it tends to become brittle in time, and the moisture in the bricks would make it peel off. It would perhaps be best first to cover the brickwork with raw linseed oil only, so as to get a grip and to stop the suction, then finish with the oxide paint.