The Chemistry of Powder and Explosives - Sciencemadness Dot Org

124 PYROTECHNICS
ride. For a grayer smoke naphthalene or anthracene is added to
the mixture. Torches for black smoke have also been used,
charged with a mixture of potassium nitrate and sulfur with
rosin or pitch and generally with such additional ingredients as
sand, powdered chalk, or glue to modify the rate of their burning.
When shells are loaded with certain high explosives which produce
no smoke (such as amatol), smoke boxes are generally inserted
in the charges in order that the artilleryman, by seeing
the smoke, may be able to judge the position and success of hitfire.
These are cylindrical pasteboard boxes containing a mixture
of arsenious oxide and red phosphorus, usually with a smali
amount of stearine or paraffin.