HIGH EXPLOSIVES. 497 



charge for shells. A large number of explosive compounds have been 

 submitted by various inventors and tested by the Ordnance Depart- 

 ment of the United States Army at the Sandy Hook Proving Grounds. 



Some of the explosive compounds submitted have given very satis- 

 factory results. Perhaps half a dozen of them would serve fairly well, 

 if nothing better could be found. The Government, however, has placed 

 its standard of excellence very high, with the hope of finding, if pos- 

 sible, something better than is possessed by other countries. 



The United States Government was one of the last to adopt a 

 smokeless powder, notwithstanding the fact that it was one of the first 

 to experiment with these new explosives. But the Departments then 

 having the matter in charge were very conservative, taking nothing 

 for granted, were uninfluenced by the example of other countries and 

 were determined that nothing but the best would be good enough for 

 Uncle Sam. The result is that this Government to-day possesses a 

 smokeless powder superior to that adopted by any other country. The 

 same policy has been manifested in the search for a high explosive 

 suitable as a bursting charge for shells. 



The tests through which a high explosive must pass before there is 

 the least hope of its meeting the requirements of the Government are 

 very severe. The inventive Yankee, having an ambition to serve the 

 Government by producing for its use a satisfactory high explosive, has 

 u difficult task before him. In the first place, the compound must be 

 perfectly stable, and to determine this it is submitted to a severe 

 heat test for a period of fifteen minutes. If it fails to stand this test 

 it is condemned at once, and goes no further. If it passes the heat 

 test satisfactorily, a quantity is then placed under a falling weight 

 or hammer to test its sensitiveness or its ability to resist shock. This 

 is determined by the height from which it is necessary for the hammer 

 to fall in order to explode the material. If the explosive proves suf- 

 ficiently insensitive to indicate that it will stand the impact or shock 

 of penetrating armor plate, it is then tested to determine its explosive 

 power. A forged steel armor-piercing shell is filled with the material 

 and armed with a very powerful exploder, which is set off by electricity. 

 The force of the explosive is shown by the number and character of the 

 fragments. Small shells are burst for fragmentation in a steel-walled 

 chamber; larger shells are buried in the sand and exploded, the frag- 

 ments being recovered by sifting the sand. 



If the number of fragments indicates a sufficiently high explosive 

 power, an armor-piercing shell is filled with the compound and fired 

 through a nickel steel plate, so thick as to almost stop the shell in 

 passing through, leaving just velocity enough to carry it a few feet 

 into a sand butt back of the plate, where it may be dug out and re- 

 covered, provided the explosive proves to be sufficiently insensitive to 



VOL. LVIII.— 32 « 



