122 Guns and Projectiles. 



an analogous nature. Now it is possible to strike the base of 

 the projectile and the sides of the gun with such force and 

 velocity as to break up their cohesion ; but this is destroying 

 the carriage and the passenger instead of conveying him quickly 

 to his legitimate destination. When we sit in a railway train 

 and the engine starts, we feel a jerk as the coupling chains are 

 extended, and the vehicles are pulled. If this jerk were 

 greater than the chains would bear, they would be broken, and 

 perhaps the carnage also, but we should, scarcely move. If the 

 engine, as it sometimes is the case, were placed behind, and it 

 shoved the carriages too rapidly, they would be smashed 

 without receiving much forward motion. This will explain 

 why, with gunpowder, or its substitutes, too great a velocity 

 of action will not answer. The chemical composition, the size 

 of the grains, the mode of ignition, all influence the rate at 

 which solid gunpowder is changed into heated gas. When it 

 is intended to burn a given quantity of powder in order to 

 communicate velocity to a projectile of particular weight, the 

 preceding circumstances have to be considered, and also the 

 best mode of packing the powder, whether it shall occupy a 

 broader or a shorter column. The length of the barrel must 

 also be proportioned to the quantity of powder and the rate at 

 which it burns. 



Hitherto, gunpowder has not been surpassed for practical 

 utility in fire-arms, but recent Austrian experiments again 

 revive the claims of gun-cotton, and perhaps other compounds, 

 as yet unknown, may prove more convenient than either. 

 Looking at this, and to other probabilities, we must not expect 

 that we are to solve for ever the problem of the best gun and 

 the best projectile. All that we can reasonably desire is, that, 

 wL other the skill of our nation is permitted to develope itself 

 in peace, or unfortunately compelled to exercise itself in war, 

 we may be amongst the foremost in science, and amongst 

 the most ready to welcome useful novelties and cast old 

 prejudies and ignorances aside. 



