To a mile) is dissected by many branching consequent streams; in its southernpart, as it ap~iroaches the Colorado river the cuesta is dissected into a belt of discontinuous hills.
The longitudinal system is discontinuous, and is subdivided into proximal, medial and distal portions.
Modifications of the system have been adopted for bridges with discontinuous spans.
The discovery of this significant looped arrangement of the morainic belts is the greatest advance in interpretation of glacial phenomena since the first suggestion of a glacial period; it is also the strongest proof that the ice here concerned was a continuous sheet of creeping land ice, and not a discontinuous series of floating icebergs, as had been supposed.
As, in succeeding members of this same series of cast irons, more of the graphite of the initial skeleton changes into cementite and thereby becomes part of the metallic matrix, so the graphite skeleton becomes progressively thinner and more discontinuous, and the matrix richer in cementite and hence in carbon and hence equivalent first to higher and higher carbon steel, such as tool steel of I carbon, file steel of 1.50%, wire-die steel of 2% carbon and then to white cast iron, which consists essentially of much cementite with little ferrite.