2018年12月大学英语四级考试听力,2018年12月大学英语四级听力美文:TheOriginofthe...

【#四六级考试# 导语】英语听力是英语四六级考试中的重要组成部分，对于中国的考生，日常英文听说机会少，缺少听力训练，所以在备考大学英语四六级时，需要加强听力的训练。针对这一情况，®文档大全网英语四六级频道特别整理听力相关文章《2018年12月大学英语四级听力美文:The Origin of the...》，供学员参考使用。预祝大家高分通过考试。

　　2018年12月大学英语四级听力美文100篇

　　英语四级听力美文第53篇:The Origin of the Refrigerators

　　By the mid—nineteenth century, the term icebox had entered the American language, but icewas still only beginning to affect the diet of ordinary citizens in the United States. The ice tradegrew with the growth of cities. Ice was used in hotels, taverns, and hospitals, and by someforward—looking city dealers in fresh meat, fresh fish, and butter. After the Civil War (1861-1865), as ice was used to refrigerate freight cars, it also came into household use. Even before 1880 half of the ice sold in New York, Philadelphia, and Baltimore, and one—third of that sold inBoston and Chicago, went to families for their own use. This had become possible because anew household convenience, the icebox, a precursor of the modern refrigerator, had beeninvented. Making an efficient icebox was not as easy as we might now suppose. In the earlynineteenth century, the knowledge of the physics of heat, which was essential to a science ofrefrigeration, was rudimentary. The commonsense notion that the best icebox was one thatprevented the ice from melting was of course mistaken, for it was the melting of the ice thatperformed the cooling. Nevertheless, early efforts to economize ice included wrapping up theice in blankets, which kept the ice from doing its job. Not until near the end of the nineteenthcentury did inventors achieve the delicate balance of insulation and circulation needed for anefficient icebox. But as early as 1803, an ingenious Maryland farmer, Thomas Moore, hadbeen on the right track. When he used an icebox of his own design to transport his butter tomarket, his butter, still fresh and hard in neat, was worth one—pound a brick. One advantageof his icebox, Moore explained, was that farmers would no longer have to travel to market atnight in order to keep their produce cool.

　　2018年12月大学英语四级听力美文100篇

2018年12月大学英语四级听力美文:The Origin of the....doc

本文来源：https://www.wddqw.com/vlp5.html