MISCELLANEOUS HINTS. 437 



grained powder, such as is sold in the small country shops, from 

 which source our friend always procured his supply ; for as soon 

 as he loaded with it the ducks came tumbling down right and 

 left. 



GLAZED POWDER. 



Some powder is glazed and some not. The comparative strength 

 of the two kinds is not much, if at all, affected by the process 

 which it undergoes in glazing, as the grains are merely triturated 

 with blacklead, to give them the 'glossy appearance which they 

 present. 



It is deemed absolutely indispensable that all military powder 

 should be glazed, to prevent the formation of too much dust by af- 

 friction in its transport from place to place ; as it is a well-esta- 

 blished fact that a charge of powder compressed into a solid, dense 

 mass, as it necessarily would be if its whole granular as well as 

 angular construction was destroyed by pulverization, must lose 

 some of its propulsion by the slowness of combustion. 



As has been remarked by Greener, "though it is possible to fire 

 powder in vacuo," still, the presence of a certain amount of air 

 in the interstices of any combustible mass will greatly facilitate 

 the rapid penetration of the flame through it, and consequently 

 increase the projectile power dependent upon its instantaneous 

 combustion. Commenting on Dupont's sporting-powder, Captain 

 Mordecai, of the Ordnance Department, remarks as follows: 

 " Dupont's very fine-grained sporting-powder, being thoroughly in- 

 corporated, free from dust, and composed of angular grains, although 

 highly glazed, far surpasses all the other kinds in quickness." 

 Further on, he again observes : " The great and uniform superiority 

 of Dupont's fine sporting-powder, even in large charges in the 

 cannon, evinces the combined effect of the most careful preparation 

 of the materials, their thorough incorporation, perfect drying, and 

 high glazing, all of which are favorable not only to the production 

 of the greatest inherent force of the composition, but to the quick 



