Safety Fuse, a tubular cord of cotton, rendered slowly combustible for communicating fire to the explosive used in blasting. The cavity in the centre of the cord is filled with some slow-burning compound, and the cord is then wound with tarred twine, and covered outside with a coating of tar. It is thus protected from moisture, and is made sufficiently firm and hard not to be cut by the fragments used in tamping. It burns about three feet in a minute. A method has been patented of introducing a combustible thread through the centre of the cord in the powder, with the view of providing another means of communicating the fire in case the powder is interrupted or the cotton of the tube does not continue to burn. For its use, see Blasting.