重囗另类BBWSeⅹHD,av狼论坛,精品一卡2卡三卡4卡乱码理论,体育生gv老师浪小辉3p警察

The origin of Refrigerators

時間:2023-05-04 19:00:01 考研英語作文 我要投稿
  • 相關推薦

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 ha

【The origin of Refrigerators】相關文章:

Origin of Christmas04-30

On the Origin of the World高中英語小作文05-02

Origin of summer monsoon rainfall identified by δ18O in precipitation04-26

利用Origin 7.0軟件處理超聲波聲速實驗數據04-28

Why are There Indica Type and Japonica Type in Rice?-History of the Studies and a View for Origin of Two Types04-26

Heterogeneous transition dynamic equations and the self-organized origin of the nesting rhythmic beddings in Panzhihua l04-28

Rare-earth and trace element imprints on the origin and tectonic setting of gabbro-diorite complex in the Pan-African be04-28

主站蜘蛛池模板: 平定县| 许昌县| 济宁市| 温泉县| 盐津县| 岳普湖县| 莆田市| 厦门市| 乌兰浩特市| 交城县| 东台市| 沾化县| 海口市| 湛江市| 防城港市| 博爱县| 漳州市| 卢湾区| 张家港市| 屯留县| 甘孜县| 张掖市| 钟山县| 兴业县| 胶州市| 定州市| 射洪县| 济阳县| 阜城县| 奎屯市| 昭觉县| 黄山市| 新田县| 舟山市| 吉木萨尔县| 土默特右旗| 玉树县| 罗田县| 海淀区| 防城港市| 石家庄市|