333,364. Stephens, A. J., (Asociacion de Productores de Yodo de Chile). July 11, 1929. Matches; striking-surfaces.-Iodine or an iodine compound, especially cuprous or plumbous iodide, is added to igniting compositions containing oxidizable substances such as chlorates, nitrates,and peroxides; or the iodine or iodine compound is added to the rubbing surface used for igniting compositions. This improves ignition or combustion. One example of igniting composition contains 50.52 per cent of potassium chlorate, 3-4 per cent of potassium bichromate, 5 per cent of sulphur or minium (Pb3O4), 10 per cent of iron oxide, 10 per cent of manganese peroxide, 10-12 per cent of quartz or glass powder, and 10-12 per cent of glue, to which 1-2 per cent of cuprous iodide is added. One example of rubbing surface relates to a mixture of 50 per cent of red phosphorus, 10 per cent of antimony sulphide, 17 per cent of kieselguhr, 5 per cent of whiting, and 18 per cent of gum arabic, in which the 50 per cent of red phosphorus is replaced by 10 per cent of red phosphorus with 5 per cent of cuprous iodide, the proportions of the other ingredients being proportionately increased. A similar effect is obtained by the addition of 1-2 per cent of cuprous iodide to potassium chlorate or perchlorate, such addition causing these salts to give up the whole of their oxygen content uniformly when heated below 300‹ C. instead of the 400‹ C. required when no such addition is made.