大学英语四级阅读的200篇: Unit 41 passage 1_大学英语阅读

大学英语四级阅读的200篇: Unit 41 passage 1

　　The first railroads, which were only a few miles long, grew until they eventually spanned the continent. Whether they were large or small their pattern was very much the same. The great iron horses followed routes worn earlier by four-legged horses and even earlier by parties of Indians. These pathways were mostly determined by geography, because man has always sought the easiest route to travel. He has found his way across plains and along meandering streams. When confronted by mountains, he has preferred to discover a pass rather than to ascend the peaks or to bore this way through them. In that sense we can say that the routes of our railroads were determined to a large extent before man ever existed.

　　The cars of the first crude trains, used before the War of 1812, were drawn by horse. These early railroads served only local needs. Sometimes they were used in connection with canals; on other occasions they performed various transportation chores for local mines or factories. They did little or nothing to

　　meet the needs of people who wished to travel. The first successful use of steam to move trains was achieved in England in 1829. A locomotive invented by George Stephenson made history when it hauled a train at the rate of 15 miles per hour. Trains were first moved by steam over American railroads inl830. By that date the Baltimore and Ohio Railroad had completed construction of its tracks from Baltimore to Ellicotts Mills, a distance