module 3 LISTENING HISTORY OF MACHINE TOOLS COMMUNICATION Listen to the CD and fill in the blanks choosing from the words in the box below. machine tools parts cutting manufacturing government engine products specialized precision inventor methods design system shapers Modern machine tools date from about 1775, when the English (a) ......................... John Wilkinson constructed a horizontal boring machine for producing internal cylindrical surfaces. In 1794 Henry Maudslay developed the first (b) ......................... . In 1830, Joseph Whitworth developed accurate measuring instruments: his work was of great value because precise (c) ......................... of measurement were necessary for the subsequent mass production of articles with interchangeable (d) ......................... . The earliest attempts to manufacture interchangeable parts occurred almost simultaneously in Europe and the United States, but the first true mass-production (e) ......................... was created by the American inventor Eli Whitney, who obtained a contract with the U.S. (f) ......................... in 1798 to produce 10,000 army muskets, all with interchangeable parts. During the 19th century, standard machine tools such as lathes, (g) ......................... , planers, grinders, saws, and milling, drilling and boring machines reached a fairly high degree of (h) ......................... , and their use became widespread in the industrializing nations. During the early part of the 20th century, machine tools were enlarged and made even more accurate and (i) ......................... in their applications. From about 1930 to 1950, more powerful and rigid machine tools were built to effectively utilize the greatly improved (j) ......................... materials that had become available. These specialized machine tools made it possible to manufacture standardized (k) ......................... very economically, using relatively unskilled labour. The machines lacked flexibility, however, and were not adaptable to a variety of products or to variations in (l) ......................... standards. However, in the past three decades engineers have developed highly versatile and accurate (m) ......................... that have been adapted to computer control, making possible the economical manufacture of products of complex (n) ......................... . Such tools are now widely used. (Adapted from Microsoft Encarta Encyclopedia) GLOSSARY attempt: tentativo musket: moschetto to occour: avvenire planer: piallatrice saw: sega unskilled labour: manodopera non specializzata 136