In France and Belgium also the compositions of the coal-mine explosives are published, but in Germany, as a rule, only a list of the constituents is given, and sometimes an upper or lower limit for one or more of the principal constituents. Moreover, it is not stated explicitly whether the explosives are intended for use in coal mines or for general blasting purposes. In the United States of America, explosives intended for use in coal mines are examined by the Bureau of Mines, which, however, has no power to prevent the use of others because regulations on this matter are made by the individual states. If they pass they are placed on the list of “Permissible Explosives.” The compositions are not published, but the class of composition is stated. Until the second half of the nineteenth century, gunpowder was practically the only explosive used on a considerable scale, and it was employed for all purposes. Consequently it does not fall into any of the classes mentioned, or rather it could be placed in several of them. Another class of explosives that has not yet been mentioned is that of the primary igniters, of which fulminate of mercury may be taken as typical. The characteristic of these is that they can be exploded or ignited by a spark or moderate friction, and consequently they can be employed to fire other, less sensitive explosives. There are, however, practically no explosives of this class which possess special or proprietary names, and consequently they are not dealt with in this dictionary. _Naini Tal, India._ 1920. CLASSIFICATION COAL-MINE EXPLOSIVES _American Permissible Explosives._ Aetna Coal Mine Powder. Bental Coal Powder. Bituminite. Black Diamond. Cameron Mine Powder. Carbonite. Coalite. Coal Special. Collier Powder. Cronite. Detonite. Du Pont Permissible. Eureka. Fort Pitt Mine Powder. Fuel-ite. Giant Coal Mine Powder. Guardian. Hecla No. 2. Hygrade Coal Powder. Kanite. Lomite. Lowinite. Meteor. Miners’ Friend. Min-ite. Monobel. Nitro Low-Flame. Red H. Trojan Coal Powder. Tunnelite. Vigorite. Xpdite. _Austrian and Hungarian._ Chloratit. Dynammon. Progressit. Titanit. _Belgian Explosifs S.G.P._ Alsilite. Antigel de Sûreté. Baelenite. Colinite antigrisouteuse. Cornil. Densite. Dynamite antigrisouteuse. Favier Explosives. Flammivore. Forcite antigrisouteuse. Fractorite. Grisoutine II. Grisoutite. Ingélite. Minerite. Minite. Minolite. Pulvérite. Sabulite antigrisouteuse. Securophore. Wallonite. Yonckite. (There were also several explosives made in Germany.) _British._