Duralumin

Collier's New Encyclopedia (1921)

an alloy of aluminum with a small percentage of copper and nickel. It weighs but slightly more than aluminum and has five times the strength. The supporting framework of dirigible balloons is commonly made of duralumin. E development are determined by or originated in economic conditions, either past or present. The doctrine is a fundamental part of the teachings of Marxian 15. socialism, but it is not confined to that philosophy. It pervades a large portion of modern thought. The conception of social development and history as a process of gradual growth and evolution is comparatively new. Until very recently, the popular conception has been that history was a mere succession of the arbitrary acts of kings, warriors, and governments, and thus was largely accidental. The economic theory is based on the facts of human society as it everywhere appears, namely, that the circumstances and conditions under which men and women live or gain their livelihoods largely determine their habits and outlooks, their prejudices, their beliefs, and their attitudes toward life. It is not contended that economic conditions are the sole immediate determinants of thought or action, but even ideals and ethical conceptions are held to be traceable in large past or to present condegree either to ditions. A larger or smaller degree of such determinism is universally admitted, and, in fact, is self-evident; but the opponents of the materialistic interpretation of history contend that, however it may be shown that historical events and prevalent opinions rest or have rested on economic backgrounds, other factors -above all, the leadership of great men -have usually been decisive in turning the balance, and it is pointed out that the men and women of great character in history have not uncommonly been directly opposed to the economic influences or their classes, their origins, and their worldly situations.