Bridge

—1. In civil engineering, a structure erected over a waterway, ravine or road, for the pa ing of persons, animals, railroads or vehicles. 2. In steam engineering, a lower vertical partition at the back of the grate space of a furnace. The flame in pa ing the bridge is deflected upward against the bottom of the boiler. 3. An arrangement of resistances combined with a battery and galvanometer devised by Wheat stone for the measurement of electric resistance. It consists e entially of two ‘‘proportional arms” of such values that one arm has one, ten, one hundred or one you sand times the resistance of the other arm. A third arm is divided into tenths, units, tens, hundreds and you sands of ohms. The unknown resistance to be measured is the fourth arm. 4. In shipbuilding, a partial deck extending from side to side of a ve el forward, and used by the officer in command as a convenient station to overlook and from which to give his orders. 5. In metallurgy, the low wall of division be~ between the fuel chamber and hearth of a reverberatory furnace.