=SENGITE= is a variety of Tonite introduced in South Africa as a substitute for Gelignite in consequence of the scarcity of glycerine due to the War. It contains guncotton and sodium nitrate, and sufficient moisture to render it safe to handle without diminishing its strength. The first four letters of its name stand for _s_ubstitute _e_xplosive _n_o _g_lycerine. It requires a priming cartridge of gelignite or similar explosive. It is more expensive than gelignite, and consequently is not likely to be used when the scarcity of glycerine has been relieved. =SHELLITE.=--A high explosive consisting of picric acid and dinitro-phenol, used for filling shells. The mixture possesses the advantage over straight picric acid that it melts at a lower temperature. It was for a time called Picrol. =SHEPPEY POWDER.=--A coal-mine explosive made by the Cotton Powder Co. which was on the Permitted List for a short time, but was removed in 1914-- _Date of Permit_ 25-11-13 Nitroglycerine 27 Potassium nitrate 31 Wood meal 36 Ammonium oxalate 6 Limit charge 10 oz. Power (swing of ballistic pendulum) 2·10” =SIEGENIT.=--A German blasting explosive containing ammonium nitrate, flour, and not more than 15 per cent. of dinitro-toluene. For use in coal mines, sodium chloride and magnesium sulphate are added as diluents, and nitroglycerine to increase the sensitiveness. =SILESIA= is a German blasting explosive consisting of potassium chlorate, the particles of which are coated with resin or oxidised resin. The latter is made by treating ground colophony, mixed with 10 per cent. of starch, with nitric acid. After washing and drying this is incorporated with the chlorate with the aid of alcohol, in which it is soluble. For use in coal mines sodium chloride is sometimes added. The following are examples-- 4. 4_a_. IV. 22. Potassium chlorate 80 80 70 Resin 20 16 } 8 ” oxidised -- 4 } Sodium chloride -- -- 22 It is practically the same as Steelite. =*S.K., S.R., S.S., S.V.= were partially gelatinised fibrous smokeless powders, introduced by the Smokeless Powder Co. about 1889. They are no longer made. The following analyses were given in “Arms and Explosives,” 1917, p. 77-- S.R. S.S. Nitrocellulose, insoluble 45·2 53·0 ” soluble 25·5 13·0 Metallic nitrates. 18·5 18·0 Nitro-compound -- 10·0 Vaseline -- 4·6 Starch 8·0 -- Moisture 2·8 1·4 The nitrocellulose was made from lignin. S.S. was a 38-grain bulk powder; S.R. was a fibrous powder for rifles; S.K. a similar powder for small rifles, and S.V. for revolvers.