The first cook. It took a long time, however, to learn how to use this gift. For centuries men lived like wild animals. Their food consisted of nuts, herbs, fruit, and the flesh of animals. Cooking was unknown, and when a wild animal was captured, the savage tore it apart and ate the raw flesh. According to one legend, a hunter, after a long tramp, succeeded in catching a rabbit. On his way home he found a smoldering fire which had been started by lightning. Throwing his rabbit on a log, he lay down and went to sleep. When he awoke, he found that his rabbit had fallen into the fire. In attempting to rescue it, the savage got some of the juice of the roasted rabbit on his fingers. By instinct, he put his burnt fingers to his mouth, and the taste was so pleasing that he immediately finished the rabbit, and this is how man learned to cook.
Reduction of metals. Ages later, man began to use fire to make metals and to form them into spears and hatchets for hunting and fighting. The alchemists, as we know, used fire in their attempts to change the base metals into gold, and today fires are burning in many furnaces producing, if not gold, metals of far greater value to the progress of civilization. Copper, bronze, iron, and steel, produced by fire, have been the stepping stones of mans progress through the ages. The chemistry involved in the extraction, purification, and alloying of metals is so interesting and of such great importance that volumes have been written on this subject.
Heating homes. We are so accustomed to living in heated homes that it is only when something goes wrong with the furnace that we give any thought to the blessed fire. To the savage shivering in his cave, however, a fire was a real blessing, even if it did fill his eyes with smoke. Keeping the home fires burning
was a difficult task for the American Indian, who delegated this to his wife. Woe be to the squaw who let the fire go out. In the wintertime, the fire was built on the ground in the center of the tent, which had a small hole in the top to act as a smokestack. Even the palaces of the wealthy in the Middle Ages were cold and damp, the fireplaces being so inefficient that only a portion of one room could be heated at a time. Not until a comparatively recent date were stoves invented, and furnaces were unknown even when your grandfather was a boy.
How fires are started and stopped. You have learned that burning is rapid oxidation which gives off light and heat. In order to start a fire, three conditions are necessary: something to burn; something to support the combustion; and a means of lighting the fuel . Having lived all his life in a home where the furnace is kept burning all winter, the average person seldom thinks of the difficulty of starting a fire.
初中英语单词表:九年级unit8-14
Yoox和NAP合并之后
《狼图腾》将代表中国角逐奥斯卡
“一带一路”官方译法
美国应乐见俄罗斯出兵叙利亚
白宫“国宴”大起底
中考易混词汇辨析:will与would
中国关于联合国成立70周年的立场文件
彭麻麻联合国演讲谈“中国梦”
中考易混词汇辨析:whole/ all
中考易混词汇辨析:all与whole
百度成Win10在华“默认搜索引擎”
中考易混词汇辨析:each, both, all, either
英国12岁女孩智商超爱因斯坦和霍金
习近平:中美将在2016年举办“中美旅游年”
胡歌传奇大戏《琅琊榜》登陆北京卫视
日本妇女压力大 帅哥帮你把泪擦
央行进一步便利“跨境双向人民币资金池”业务
英语中表达复数,真的只是单词加s吗?
掉进水里也能浮在水面的手机
习近平访美49项成果清单
中国领导人联合国发声记录
习近平在中美省州长论坛上的讲话(全文)
中考易混词汇辨析:big/ large/ great
亚开行下调亚洲今年经济增长预期
中考易混词汇辨析:every 与 each
盘点亚洲各地如何庆中秋
中考易混词汇辨析:in, after, behind
澳大利亚新总理是微笑的刺客
奥巴马同意与普京在纽约举行会晤
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |