At 2.50 to 3 metres distance from the exterior border, sink a mining hole, about 5 or 6 centimetres in diameter, and 2 or 3 metres in depth. ... This cylinder is fixed to an ordinary mining fuse, which goes down a certain depth to insure the combustion of the powder. ... When it touches the surface, hold it perfectly still, and pour sand into the hole until it is quite full; there is no need to compress or plug the sandanbsp;...
|Title||:||The Annual of Scientific Discovery: Or, Year-book of Facts in Science and Art|