Dynamite frozen

Since none of the above listed "antifreezes was really good, many. industrialists preferred not to use them at all, but just defrost the ordinary Dynamite in winter or store it in a warm magazine. This situation lasted until 1902 when a severe exp In in Greisenau Mine, Germany, was caused by frozen Dynamite. This disaster produced the renewal of research on antifreezes and in 1903 the SA de Poudres et Dynamites of France introduced DNT TNT as antifreezes. These compds did not reduce appreciably the strength of Dynamites and were satisfactory from this point of view. They, however, did not lower the ft p of NG sufficiently for use in very cold weather... 

Dynamite, efficiency of, 118. frozen dynamite, 116. gelatine dynamite, 119. properties of kieselguhr dynamite, 116. Reid Borland s carbo-dynamite, 119. Rhenish dynamite, 119. various kinds of 119. 

The first-named cartridges generally have tlieir paper covering removed and are forced into the borehole. The fuse cartridges serve for tire reception of the percussion cap, that is the cpiick match which is contained in the percussion cap. The cartridges of frozen dynamite, in addition to.ordinary dynamite, contain a mixture of saltpetre and ro.sin or of potassium chlorate and antimony sulphide or similar ingredients, which are first ignited by the pci-cussion cap, and these cause the frozen dynamite to explode. 

At temperatures under 8° the nitro-glycerine in the dynamite freezes, and the latter congeals or hardens. Frozen dynamite is thawed in the same way as frozen niti-o-glycerine and the samo precautionary measures must l)c taken. 

Frozen (that is entirely, not partly, frozen) dynamite is less sensitive to blow, shock, shot, and heat than non-frozen dynamite. The reasons for this are of course the same as in the case of frozen nitroglycerine. 

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