This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1917 Excerpt: ...using the hand pump. It is evident that the force, in whatever way obtained, which effects counter recoil also acts during recoil and that it forms a part of the total resistance R to recoil. 191. Resistance of the Counter Recoil Springs or Air Cylinders. The resistance 5 of a coiled spring varies directly with the compression of the spring. Representing by G the force required to compress the spring, when free, over the first unit of length, the resistance of the spring at any length of compression x is S = Gx. If the spring has an initial compression so that it exerts a resistance G', the resistance after further compression over a length x becomes S=G'+Gx (18) For the counter recoil springs of a gun carriage, G' represents the residual pressure in the spring when the gun is in battery, and x represents any length of recoil. The resistance of the spring at any point may therefbre be determined from Eq. (18). Air compressed by a piston in a cylinder acts as a spring and follows the law given by Eq. (18). When an air cylinder is used S becomes the total pressure of the air over the effective area of the air piston. 192. Total Resistance to Recoil.--The total resistance to recoil is composed of the resistance opposed by the brake, the resistance due to friction, the resistance--either plus or minus--due to the inclination of the top of the chassis or the recoil slides and the resistance due to the counter-recoil springs or air cylinders if there are such included in the recoil system. Let W be the weight of the moving parts; M the mass of the moving parts; / the coefficient of friction; a the angle of inclination of the chassis rails, or of the recoil slides; S the resistance of the springs or air cylinders at any point of recoil; P the total resistance of t...