大學英語六級考試拓展閱讀-背誦美文74

        雕龍文庫 分享 時間: 收藏本文

        大學英語六級考試拓展閱讀-背誦美文74

          74 The History of Chemistry

          Chemistry did not emerge as a science until after the scientific revolution in the seventeenth century and then only rather slowly and laboriously. But chemical knowdedge is as old as history, being almost entirely concerned with the practical arts of living. Cooking is essentially a chemical process; so is the melting of metals and the administration of drugs and poisons. This basic chemical knowledge, which was applied in most cases as a rule of thumb, was nevertheless dependent on previous experiment. It also served to stimulate a fundamental curiosity about the processes themselves. New information was always being gained as artisans improved techniques to gain better results. The development of a scientific approach to chemistry was, however, hampered by several factors. The most serious problem was the vast range of material available and the consequent difficulty of organizing it into some system. In addition, there were social and intellectual difficulites, chemistry is nothing if not practical; those who practice it must use their hands, they must have a certain practical flair. Yet in many ancient civilizations, practical tasks were primarily the province of a slave population. The thinker or philosopher stood apart from this mundane world, where the practical arts appeared to lack any intellectual content or interest. The final problem for early chemical science was the element of secrecy. Experts in specific trades had developed their own techniques and guarded their knowledge to prevent others from stealing their livelihood. Another factor that contributed to secrecy was the esoteric nature of the knowledge of a alchemists, who were trying to transform base metals into gold or were concerned with the hunt for the elixir that would bestow the blessing of eternal life. In one sense, the second of these was the more serious impediment because the records of the chemical processes that early alchemists had discovered were often written down in symbolic language intelligible to very few or in symbols that were purposely obscure.

          

          74 The History of Chemistry

          Chemistry did not emerge as a science until after the scientific revolution in the seventeenth century and then only rather slowly and laboriously. But chemical knowdedge is as old as history, being almost entirely concerned with the practical arts of living. Cooking is essentially a chemical process; so is the melting of metals and the administration of drugs and poisons. This basic chemical knowledge, which was applied in most cases as a rule of thumb, was nevertheless dependent on previous experiment. It also served to stimulate a fundamental curiosity about the processes themselves. New information was always being gained as artisans improved techniques to gain better results. The development of a scientific approach to chemistry was, however, hampered by several factors. The most serious problem was the vast range of material available and the consequent difficulty of organizing it into some system. In addition, there were social and intellectual difficulites, chemistry is nothing if not practical; those who practice it must use their hands, they must have a certain practical flair. Yet in many ancient civilizations, practical tasks were primarily the province of a slave population. The thinker or philosopher stood apart from this mundane world, where the practical arts appeared to lack any intellectual content or interest. The final problem for early chemical science was the element of secrecy. Experts in specific trades had developed their own techniques and guarded their knowledge to prevent others from stealing their livelihood. Another factor that contributed to secrecy was the esoteric nature of the knowledge of a alchemists, who were trying to transform base metals into gold or were concerned with the hunt for the elixir that would bestow the blessing of eternal life. In one sense, the second of these was the more serious impediment because the records of the chemical processes that early alchemists had discovered were often written down in symbolic language intelligible to very few or in symbols that were purposely obscure.

          

        周易 易經 代理招生 二手車 網絡營銷 旅游攻略 非物質文化遺產 查字典 精雕圖 戲曲下載 抖音代運營 易學網 互聯網資訊 成語 詩詞 工商注冊 抖音帶貨 云南旅游網 網絡游戲 代理記賬 短視頻運營 在線題庫 國學網 抖音運營 雕龍客 雕塑 奇石 散文 常用文書 河北生活網 好書推薦 游戲攻略 心理測試 石家莊人才網 考研真題 漢語知識 心理咨詢 手游安卓版下載 興趣愛好 網絡知識 十大品牌排行榜 商標交易 單機游戲下載 短視頻代運營 寶寶起名 范文網 電商設計 免費發布信息 服裝服飾 律師咨詢 搜救犬 Chat GPT中文版 經典范文 優質范文 工作總結 二手車估價 實用范文 石家莊點痣 養花 名酒回收 石家莊代理記賬 女士發型 搜搜作文 鋼琴入門指法教程 詞典 讀后感 玄機派 企業服務 法律咨詢 chatGPT國內版 chatGPT官網 勵志名言 文玩 語料庫 游戲推薦 男士發型 高考作文 PS修圖 兒童文學 工作計劃 舟舟培訓 IT教程 手機游戲推薦排行榜 暖通,電地暖, 女性健康 苗木供應 ps素材庫 短視頻培訓 優秀個人博客 包裝網 創業賺錢 養生 民間借貸律師 綠色軟件 安卓手機游戲 手機軟件下載 手機游戲下載 單機游戲大全 石家莊論壇 網賺 職業培訓 資格考試 成語大全 英語培訓 藝術培訓 少兒培訓 苗木網 雕塑網 好玩的手機游戲推薦 漢語詞典 中國機械網 美文欣賞 紅樓夢 道德經 標準件 電地暖 鮮花 書包網 英語培訓機構 電商運營
        亚洲精品动漫在线| 亚洲三级电影网址| 亚洲精品中文字幕麻豆| 亚洲av无码国产精品夜色午夜 | 亚洲区日韩精品中文字幕| 亚洲人成在线精品| 亚洲国产午夜电影在线入口| 亚洲最新在线视频| 亚洲喷奶水中文字幕电影| 亚洲乱码一区av春药高潮| 亚洲六月丁香六月婷婷色伊人| 亚洲国产精品综合久久2007 | 久久精品国产亚洲AV天海翼| 亚洲一久久久久久久久| 亚洲精品无码成人| 亚洲AV无码专区在线电影成人| 亚洲精品无码专区久久| 自拍偷自拍亚洲精品偷一| www.亚洲色图| 亚洲V无码一区二区三区四区观看 亚洲αv久久久噜噜噜噜噜 | 亚洲大片免费观看| 99久久婷婷国产综合亚洲| 亚洲中文字幕久久精品无码A| 亚洲卡一卡二卡乱码新区| 亚洲日韩精品无码专区| 亚洲AV无码资源在线观看| 亚洲第一区在线观看| 久久亚洲中文字幕精品一区| 国产亚洲综合色就色| 亚洲天堂中文资源| 亚洲国产成人综合| 亚洲人成人无码.www石榴 | 亚洲AV无码成人网站久久精品大 | 亚洲欧洲av综合色无码| 日韩亚洲人成在线综合| 亚洲最大AV网站在线观看| 亚洲国产精品久久久久婷婷软件 | 亚洲欧洲自拍拍偷精品 美利坚| 天天爽亚洲中文字幕| 亚洲AV无码一区二区大桥未久 | 亚洲av成本人无码网站|