Both sides of the canvas material of the canoe should be painted. The object in painting the inside is to prevent any water getting between the framework and the skin and thus rotting the canvas. Particular attention must be paid to all inside corners and edges of the stringers; the frame also must be painted before stretching the skin. There is nothing better than ordinary paint, but see that the white lead is good and not half whiting. Use plenty of boiled oil for the last coat, as salt water tends to harden paint. There is not much difference as to the durability regarding the effects of salt and freshwater.