托福阅读什么难度.docx

of heat, which was essential to a science of refrigeration,was rudimentary. The commonsense notion that the best icebox was one that prevented the icefrom melting was of course mistaken, for it was the melting of the ice that performed the , early efforts to economize ice included wrapping the ice in blankets, which kept theice from doing its job. Not until near the end of the nineteenth century did inventors achieve thedelicate balance of insulation and circulation needed for an efficient icebox.










But as early as 1803, an ingenious Maryland farmer, Thomas Moore, had been on the righttrack. He owned a farm about twenty miles outside the city of Washington, for which the villageof Georgetown was the market center. When he used an icebox of his own design to transport hisbutter to market, he found that customers would pass up the rapidly melting stuff in the tubs ofhis competitors to pay a premium price for his butter, still fresh and hard in neat, one-poundbricks. One advantage of his icebox, Moore explained, was that farmers would no longer have totravel to market at night in order to keep their produce cool.
1. What does the passage mainly discuss?
(A) The influence of ice on the diet
(B) The development of refrigeration
(C) The transportation of goods to market
(D) Sources of ice in the nineteenth century
2. According to the passage , when did the word icebox become part of the language of the










United States?
(A) in 1803
(B) sometime before 1850
(C) during the ci