There are two suitable cements that will withstand oil and heat. The first is made by separating the white from the yolk of an egg, and mixing the former to a stiff paste with powdered quicklime. The second cement is made by boiling together 5 parts of water, 1 part of caustic soda, and:! parts of resin. When the resin is dissolved, the liquid is mixed with half its weight of plaster-of-Paris, and at once used, as both cements set hard in a very short time.