Explosives That Must Be Shocked

Home explosives, such as dynamite, nitroglycerul, gun cottou, picric acid aud the new Germán military powder, when simply heated, burn qnietly if freely exposed, ov, if coniined, explode only at the spot where heat is applied, without tlie whole uiass taking part in the explosión. According to H. Blitz. this is probably because they are bad condnctors of their own explosivo wave. If, however, the same substances are subjected to a violent shock by the explosión in their inidst of initial chafgeá of mercury fulmínate, the shock apparently affects all the molecnles of the explosive at once, and the whole mass of the lattcr explodes with a violence that