首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
By the mid-nineteenth century, the term "icebox" had entered the American language, but ice was still only beginning to affect t
By the mid-nineteenth century, the term "icebox" had entered the American language, but ice was still only beginning to affect t
admin
2010-09-25
98
问题
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(酒馆), 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 fridge, 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(未发展的). 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.
What was essential to a science of refrigeration ac. cording to the passage?
选项
答案
Knowledge of the physics of heat.
解析
由题干关键词a science of refrigeration定位到原文第二段第二句话,...the knowledge of the physics of heat, which was essential to a science of refrigeration直接给出了问题的答案。
转载请注明原文地址:https://kaotiyun.com/show/xyz7777K
0
大学英语六级
相关试题推荐
ThepeopleoftheUSAhavebeenopposedtoacentralizedgovernmentsincelongbeforetheRevolutionof1776.Whenthe13coloni
Emotionsaredefinedasstrong,relativelyuncontrolledfeelingsthataffectourbehavior.Everyoneexperiencesawiderangeof
Longbeforethefirst【B1】______arrivedinAmerican,astrangelookinganimallivedonthewestern【B2】______.Itlookedsomewha
Whenyoustarttalkingaboutgoodandhadmannersyouimmediatelystartmeetingdifficulties.Manypeoplejustcannotagreewhat
Agreatmanycitiesareexperiencingdifficultieswhicharenothingnewinthehistoryofcities,exceptforintheir【S1】
Agreatmanycitiesareexperiencingdifficultieswhicharenothingnewinthehistoryofcities,exceptforintheir【S1】
A、She’stired.B、She’sgenerous.C、She’srich.D、She’sintelligent.D女士说Julia考试考了最高的分数(hadthehighestgrade),男士说这个考试对Julia来说可能是
Martinbeggedhismothertopardonhim,______(保证以后考试不现作弊了).
Thearmycommander______astateofemergencyinthatareaafterseveraloutbreaksofsuicidebombs.
随机试题
Wheredidthemoviesbegin?ItisoftensaidthattheyareanAmericaninvention.Itisnotentirelytrue.Themotionpictureha
适用于招标人愿意较深入地介入设计控制及对设计和施工进行相互协调管理,并希望分散承担风险的情况的是()。
【背景资料】某机电安装工程项目,业主通过公开招标方式选择了某机电安装公司,双方签订了机电安装工程施工总承包合同,施工总承包企业又选择了一家劳务分包公司,将某分部工程的劳务作业分包给该劳务分包公司。在施工过程中发生如下事件。事件一:由于业主供应的工程材料
影响营业利润金额大小的项目有()。
乙公司是甲公司的全资子公司,20×2年甲公司、乙公司有如下业务:(1)甲公司从乙公司购入在建厂房一幢,价款1850万元,甲公司通过银行转账1800万元,其他款项用公司产品抵偿;(2)甲公司从建材市场为在建厂房购进建筑材料一批,价款为19
物流信息的有效管理是现代化管理的基础和依据。()
艾里克森认为成年后期(50岁以后)的主要发展任务是()。
自1948年12月发行第一套人民币以来,中国人民银行已陆续发行五套人民币。第五套人民币是由中国人民银行首次完全独立设计与印制的货币,它标志着中国货币的设计印制体系已经成熟,印制技术达到国际先进水平。第五套人民币应用了多种具有国际先进水平的防伪技术,其中首次
某同学在校园网访问因特网,从该同学打开计算机电源到使用命令ftp202.38.70.25连通文件服务器的过程中,()协议可能没有使用到。
Readthefollowingarticleinwhichfivepeopletalkaboutthefuture.ForQuestion61to65,matchthenameofeachspeakerto
最新回复
(
0
)