The retrograde motion impressed upon cannon by the discharge is termed the recoil.
2. What causes the recoil of a piece?
The gas produced by the ignition of the charge in the bore, expanding with equal force in every direction, finds only two ways of escape (the muzzle and vent); the pressure upon these points will therefore cease, while it will be proportionally increased upon the parts directly opposite, that is, the breech and the lower part of the first reinforce, producing in the first case the recoil, and in the other, indirectly, the dipping of the muzzle.
3. How far does a gun usually recoil?
This depends entirely upon the nature and inclination of the ground upon which the carriage stands, the situation of the trunnions, angle of elevation, comparative weight of the gun and carriage, and upon the strength of the charge.
4. What proportion does the velocity of the recoil of a piece bear to that of a ball?
The proportion is inversely as their weights, or their masses.
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5. What proportion exists between the pressure acting upon the part of the bore of a piece directly opposite the vent, and that which occasions the recoil?
As the square of the diameter of the vent is to the square of that of the shot.