- 1、本文档共6页,可阅读全部内容。
- 2、有哪些信誉好的足球投注网站(book118)网站文档一经付费(服务费),不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
- 3、本站所有内容均由合作方或网友上传,本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺!文档内容仅供研究参考,付费前请自行鉴别。如您付费,意味着您自己接受本站规则且自行承担风险,本站不退款、不进行额外附加服务;查看《如何避免下载的几个坑》。如果您已付费下载过本站文档,您可以点击 这里二次下载。
- 4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“版权申诉”(推荐),也可以打举报电话:400-050-0827(电话支持时间:9:00-18:30)。
查看更多
社会学
Passage 1
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 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 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, an 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 ha
您可能关注的文档
- OLT维护手册OLT维护手册.doc
- OMT软件故障代码OMT软件故障代码.doc
- oo企业成长的烦恼oo企业成长的烦恼.doc
- OM4多模光纤OM4多模光纤.doc
- OOS调查指南OOS调查指南.doc
- OPC应用程序入门OPC应用程序入门.doc
- openssl安装openssl安装.doc
- OPI甲油色号大全OPI甲油色号大全.doc
- oracle基础oracle基础.doc
- ORACLE 实验大作业ORACLE 实验大作业.doc
- 《建设项目业主方的质量管理研究》.docx
- 科技防控:守护丰收-新技术应对农作物病虫害.pptx
- 完整版天津纺织集团(控股)有限公司招聘3人高频100题难、易错点模拟试题附带答案完整题库含答案(培优.docx
- 完整版天津矢崎汽车配件有限公司招聘3人高频100题难、易错点模拟试题附带答案题库大全含答案(轻巧夺冠.docx
- 《基于KRIF模型构建ICU护士绩效考核指标体系的研究》.docx
- 完整版天津纺织集团(控股)有限公司招聘(高频重点提升专题训练)共100题附带答案及答案【全国使用】.docx
- 2025年北师版九年级物理寒假复习 第17讲《12.3串、并联电路中的电阻关系》.docx
- 完整版天津纺织集团(控股)有限公司定向招聘历年高频难、易错点模拟试题附带答案题库附答案【培优】.docx
- 完整版天津源泰德润钢管制造集团有限公司招聘71人公开引进高层次人才笔试参考题库答案王牌题库及答案(名.docx
- 《基于关键链技术的大型粮食物流园区进度风险控制研究》.docx
文档评论(0)