新东方优美短文背诵 Unit30:The origin of Refrigerators
新东方优美背诵短文50篇 Unit30:The origin of Refrigerators
30 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.
冰箱的由来
直到19世纪中期,"冰箱"这个名词才进入了美国语言,但冰仅仅只是开始影响美国普通市民的饮食。冰的买卖随着城市的发展而发展。
冰被用在旅馆、酒馆、医院以及被一些有眼光的城市商人用于肉、鱼和黄油的保鲜。内战(1861-1865)之后,冰被用于冷藏货车,同时也进入了民用。
甚至在1880年前,半数在纽约、费城和巴尔的摩销售的冰,三分之一
在波士顿和芝加哥销售的冰进入家庭使用,因为一种新的家庭设备,冰箱,即现代冰箱的前身,被发明了。制造一台有效率的冰箱不像我们想象的那么简单。
19世纪早期,关于对冷藏科学至关重要的热物理知识是很浅陋的。认为最好的冰箱应该防止冰的融化这样一个
普遍的观点显然是错误的,因为正是冰的融化起了制冷作用。早期为节省冰的努力,包括用毯子把冰包起来,使得冰不能发挥它的作用。直到近19
世纪末,发明家们才成功地找到有效率的冰箱所需要的精确的隔热和循环的精确平衡。但早在1803年,一位有发明天才的
马里兰农场主,托马斯?莫尔,找到了正确方法。他拥有一个农场,离华盛顿约20英里,那里的乔治镇村庄是集市中心。
当他用自己设计的冰箱运送黄油去市场时,他发现顾客们会走过装在竞争者桶里那些迅速融化的黄油而给他比市价更高的价格买他仍然新鲜坚硬,整
齐地切成一磅一块的黄油。莫尔说他的冰箱的一个好处是使得农民们不必在夜里上路去市场以保持他们产品的低温。
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