The ballast consists of such materials as broken stone, furnace slag, gravel, cinders or earth, the lower layers commonly consisting of coarser materials than the top ones, and its purpose is to provide a firm, well-drained foundation in which the sleepers or crossties may be embedded and held in place, and by which the weight of the track and the trains may be distributed over the road-bed.
The weight of ballast in the short arms of the bascules is 365 tons.
Flint (valuable for railway ballast) occurs in immense quantities about Wymore and Blue Springs.
The weight required to cause the downward motion is obtained either by means of the material which has to be transported to the bottom of the hill or by water ballast, while to aid and regulate the motion generally steam or electric motors are arranged to act on the main drums, round which the cable is passed with a sufficient number of turns to prevent slipping.
The intervals between the sleepers are filled in level with ballast, 12'2' FIG.
10.7 in.); depth of ballast under sleepers, o mo m.
Deep, never less than 2 ft., should consist of five parts rich turfy loam, one part old lime rubbish or broken bricks, including a little wood ashes or burnt earth (ballast), one part broken charcoal, and about one part of half-inch bones, the whole being thoroughly mixed, and kept dryish till used.
Per ton; and in periods of great trade depression wheat is carried from New York to Liverpool as ballast, being paid for by the ship-owner.
1 C represents the instrument used for guineas, the circular plates A representing plates of lead, which are used as ballast when lighter coins than guineas are examined.
It is usually made of glass, the lower bulb being loaded with mercury or small shot which serves as ballast, causing the instrument to float with the stem vertical.
All through his life he navigated the Transcendental sea, piloted by a clear moral sense, warned off the rocks by the saving grace of humour, and kept from capsizing by a good ballast of New England prudence.
These allies were said to be the dynastic and monarchical ballast, and in some sort the dynastic guarantees of liberalism in the eyes of the court.
From falling on to the platform, ballast, &c.: - (a) When entering trains.
When water ballast is employed the water is filled into a tank in the bottom of the wagon or car, its quantity, if passengers are carried, being regulated by the number ascending or descending.
There are limestone quarries in nearly two-thirds of the counties and great quantities of the stone are used for flux in the iron furnaces, for making quicklime, for railway ballast and for road making.
These are unfitted for garden purposes until improved by draining, liming, trenching and the addition of porous materials, such as ashes, burnt ballast or sand, but when thoroughly improved they are very fertile and less liable to become exhausted than most other soils.