Car Couplers

The old method of coupling railway cars with a link and a pin has been abandoned for pa enger cars and in part for freight cars. This will be hastened by a law, pa ed 1893, requiring all cars employed in interstate traffic to be equipped with automatic couplers before Jan. 1, 1898. On June 30, 1893, out of 31,384 pa enger cars in the U. S., 30,446 had automatic couplers, but out of an aggregate of 1,013,307 IMG:content-0737.jpg:[graphic][merged small][merged small] a P 3z 2. To reduce equation (2) make y-z-, substitute and rep3 duce to form z+qz3---o (3). 27 3. Equation (3) solved as a quadratic gives values of z3. 4. One root being known, equation (2) or (1) become quadratic and remaining roots can be found. 5. If the roots of the cubic are all real and unequal this rule gives imaginary terms in the value of z. These can, however, be resolved by the analysis of imaginaries.