The ingredients are pulverized separately, then mixed together cautiously, and a small amount, e.g., 5 to 10 g., is placed between waxed papers. Then the whole is covered with an alcoholic shellac solution. Before the shellac dries, sand is sprinkled on the top and bottom surfaces of the small packet, so that it will not slip off the rail when the car wheel rolls over it and causes it to explode.
地址：山东省烟台市开发区南昌大街48号
