MODERN EXPLOSIVES. 797 



accounts given what are the precise causes of such disasters, but there 

 is reason to believe that ignorance is prolific ; that many persons have 

 only a vague knowledge of the qualities of nitro-glycerine, can not 

 recognize it when they see it, and are not acquainted with the various 

 forms in which it is compounded or with the peculiar dangers of hand- 

 ling it carelessly. Nitro-glycerine itself is a dense, yellowish liquid, 

 but, in order to diminish the danger attending its use, fine earth, ground 

 mica, sawdust, or some similar powder, is saturated with it, and thus 

 the various blasting-powders known as dynamite, mica-powder, dualin, 

 rend-rock, etc., are formed. These compounds can be transported with 

 comparative safety. But the nitro-glycerine easily drains off from the 

 powder and oozes from any crevice in the vessel in which the com- 

 pound is kept. Drops of it thus bedewing the edges of a box may 

 very easily be mistaken for oil escaping, and if workmen ignorantly 

 endeavor to nail the box tighter or to open it for examination there will 

 be a disastrous explosion. Several have occurred in past years in this 

 way. The victims knew, no doubt, that nitro-glycerine (or the com- 

 pounds) may be exploded by a blow (contact with fire is not needful), 

 but they did not suspect that the innocent-looking oil was nitro-gly- 

 cerine. Why should not youth be taught in the schools somewhat of 

 the practical dangers of these substances which are coming into such 

 common use ? They would pursue the study with interest, especially 

 if there were judicious experiments. A Missouri story is that a teacher 

 confiscated a small metal box which a pupil was playing with in school 

 hours, and, thinking it contained chewing-gum, tried to break it open 

 with a hammer. It was a dynamite torpedo of the kind used on the 

 railroad-track as a danger-signal, and large bits of it had to be cut out 

 of the lady's cheek. Would it not have been well if she had known 

 somewhat of the aspect of torpedoes ? Was it not more important to 

 the journeyman plumber who threw the lighted match into the pan of 

 camphene, mistaking it for water, by which the great printing estab- 

 lishment of Franklin Square was burned some twenty-eight years ago, 

 to know camphene by sight than to have memorized many of the mat- 

 ters prominent in a public-school course ? Surely workmen, especially 

 " raw hands " in establishments where these things are used, should be 

 systematically instructed in advance, and the courts are now enforcing 

 this principle. Two lawsuits were heard during 1880, where managers 

 of mining companies introduced blasting-powder as a substitute for 

 gunpowder, without specially instructing the workmen as to the change 

 and the new precautions they ought to take. The workmen used the 

 powder improperly, and some of them were badly hurt. The victims 

 brought suit for damages, and the companies retorted that the disas- 

 ters were due to carelessness of the men. Both courts said that the 

 proprietors of mines have a right to introduce a more effective powder, 

 but they are bound to give their men judicious instructions and cau- 

 tions, and to furnish them with any implements or apparatus appro- 



