免费黄网站-免费黄网站在线看-免费黄色-免费黄色a-亚洲va欧美va国产-亚洲va中文字幕欧美不卡

手機版

2011雅思備考范文背誦篇(一)

閱讀 :
The origin of Refrigerators
  By the mid-nineteenth century, the term “icebox” had entered the American language, but ice was still only beginning to affect the diet of ordinary citizens in the United States. The ice trade grew with the growth of cities. Ice was used in hotels, taverns, and hospitals, and by some forward-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 in Boston and Chicago, went to families for their own use. This had become possible because a new household convenience, the icebox, a precursor of the modern refrigerator, had been invented.
  Making an efficient icebox was not as easy as we might now suppose. In the early nineteenth century, the knowledge of the physics of heat, which was essential to a science of refrigeration, was rudimentary. The commonsense notion that the best icebox was one that prevented the ice from melting was of course mistaken, for it was the melting of the ice that performed the cooling. Nevertheless, early efforts to economize ice included wrapping up the ice in blankets, which kept the ice from doing its job. Not until near the end of the nineteenth century did inventors achieve the delicate balance of insulation and circulation needed for an efficient icebox.
  But as early as 1803, and ingenious Maryland farmer, Thomas Moore, had been on the right track. He owned a farm about twenty miles outside the city of Washington, for which the village of Georgetown was the market center. When he used an icebox of his own design to transport his butter to market, he found that customers would pass up the rapidly melting stuff in the tubs of his competitors to pay a premium price for his butter, still fresh and hard in neat, one-pound bricks. One advantage of his icebox, Moore explained, was that farmers would no longer have to travel to market at night in order to keep their produce cool.

更多 雅思作文雅思寫作雅思范文雅思作文范文、雅思高分范文雅思作文評分標準

請繼續關注 英語作文大全

本文標題:2011雅思備考范文背誦篇(一) - 雅思作文_雅思寫作_雅思范文
本文地址:http://www.hengchuai.cn/writing/englishtest/ielts/32177.html

相關文章

你可能感興趣
主站蜘蛛池模板: 一级一级毛片免费播放 | 中文字幕一区视频一线 | 久久精品国产第一区二区 | 国产一级毛片一区二区三区 | 欧美一线高本道高清在线 | 高清日本在线成人免费视频 | 欧美高清色视频在线播放 | 精品手机在线 | 男女生性毛片免费观看 | 亚洲欧美精品中字久久99 | 欧美在线观看免费一区视频 | 久久com| 在线播放国产一区二区三区 | 精品国产91久久久久 | 精品亚洲综合久久中文字幕 | 免费一级欧美片在线观免看 | 成人精品视频一区二区在线 | 91精品国| 日本在线观看www免费 | 欧美午夜免费一级毛片 | 国产精品免费_区二区三区观看 | 久久九九亚洲精品 | 波多野结衣视频免费在线观看 | 日韩经典中文字幕 | 欧美黄a | 亚洲精品区在线播放一区二区 | 九九视频在线看精品 | 国产亚洲欧美成人久久片 | 国产成人女人在线视频观看 | 女在床上被男的插爽叫视频 | 欧美日韩另类视频 | 一区二区三区在线观看视频 | 国产a毛片 | 日本理论在线播放 | 男人天堂视频网 | 欧美三级香港三级日本三级 | 日韩一区视频在线 | 国产激情一区二区三区在线观看 | 五月激激激综合网色播免费 | 91免费永久国产在线观看 | 手机看片神马午夜片 |