To prevent birds' eggs cracking or crumbling after they are blown, well rinse them out with corrosive sublimate dissolved in spirit of wine (a few grains to the ounce); this is a deadly poison. Insert a small quantity into the egg by means of a glass egg-blower with a bulb, then shake the egg so that the solution comes into contact with all the inside skin. Now draw the solution out of the egg by the blower, and return it to the bottle. Now place the egg with the hole resting upon blotting-paper, so that the last drop or two may be drawn out, and finally cover the hole with a small piece of gummed paper. Water containing a few drops of oil of cloves may be used in place of the sublimate if desired.