Oxigênio, alumínio, silício, ferro e cobre em Mumford (1934)

Aluminum is the third most abundant element on the earth’s crust, following oxygen and silicon; but at present it is manufactured chiefly from its hydrated oxide, bauxite. If the extraction of aluminum from clay is not yet commercially feasible, no one can doubt that an effective means will eventually be found: hence the supply of aluminum is practically inexhaustible, all the more because its slow oxidation permits society to build up steadily a steady reserve of scrap metal. This entire development has taken place over a period of little more than forty years, those same forty years that saw the introduction of central power plants and multiple motor installations in factories; and while copper production in the last twenty years has increased a good fifty per cent, aluminum production has increased during the same period 316 per cent. Everything from typewriter frames to airplanes, from cooking vessels to furniture, can now be made of aluminum and its stronger alloys. With aluminum, a new standard of lightness is set: a dead weight is lifted from all forms of locomotion, and the new aluminum cars for railroads can attain a higher speed with a smaller output of power. If one of the great achievements of the paleotechnic period was the translation of clumsy wooden machines into stronger and more accurate iron ones, one of the chief tasks of the neotechnic period is to translate [231] heavy iron forms into lighter aluminum ones. And just as the technique of water-power and electricity had an effect in reorganizing even the coal-consumption and steam-production of power plants, so the lightness of aluminum is a challenge to more careful and more accurate design in such machines and utilities as still use iron and steel. The gross over-sizing of standard dimensions, with an excessive factor of safety based upon a judicious allowance for ignorance, is intolerable in the finer design of airplanes; and the calculations of the airplane engineer must in the end react back upon the design of bridges, cranes, steel-buildings: in fact, such a reaction is already in evidence. Instead of bigness and heaviness being a happy distinction, these qualities are now recognized as handicaps: lightness and compactness are the emergent qualities of the neotechnic era. (Mumford 1934:230-1)

MUMFORD, Lewis. 1934. Technique and civilization. New York: Harcourt, Brace and Company.