An 18th-century account of how Newton developed the theory of gravity was posted to the Web Monday, making the fragile paper manuscript widely available to the public for the first time.
Newton's encounter with the apple ranks among science's most celebrated anecdotes, and it can now be read in the faded cursive script in which it was recorded by William Stukeley, Newton's contemporary.
Royal Society librarian Keith Moore said the apple story has resonated for centuries because it packs in so much — an illustration of how modern science works, an implicit reference to the solar system and even an allusion to the Bible.
When Newton describes the process of observing a falling apple and guessing at the principle behind it "he's talking about the scientific method," Moore said.
"Also the shape of the apple recalls the planet — it's round — and of course the apple falling from the tree does indeed hark back to the story of Adam and Eve, and Newton as a religious man would have found that quite apt."
The incident occurred in the mid-1660s, when Newton retreated to his family home in northern England after an outbreak of the plague closed the University of Cambridge, where he had been studying.
Stukeley's manuscript recounts a spring afternoon in 1726 when the famous scientist shared the story over tea "under the shade of some apple trees."
Stukeley wrote that Newton told him the notion of gravity popped into the scientist's mind as he was sitting in the same situation.
"It was occasion'd by the fall of an apple, as he sat in contemplative mood. Why should that apple always descend perpendicularly to the ground, thought he to himself ... Why should it not go sideways, or upwards? But constantly to the earth's center?" Stukeley wrote. "Assuredly, the reason is, that the earth draws it. There must be a drawing power in matter."
Stukeley's account on the Royal Society's Web site joins notes from Newton's 17th-century scientific rival Robert Hooke — documents that were lost for several hundred years before their recent discovery in a house in England.
它总是垂直下落——苹果正是这样启发了艾萨克•牛顿。
本周一，一份有关牛顿是如何发现万有引力定律的18世纪的手稿被传到网上，让不易保存的纸质手稿内容首次在网上与公众见面。
牛顿与苹果的故事是最著名的科学轶事之一，现在这个故事竟可以在褪了色的手写稿中读到，这份手稿的内容是由与牛顿同时代的（科学家）威廉•斯蒂克利记录的。
皇家学会图书馆馆长基斯•摩尔说，苹果落地的故事已经流传了几个世纪，因为它的意义十分重大——它不仅奠定了现代科学的根基，暗示了太阳系的运行原理，甚至还暗指了《圣经》。
摩尔说，当牛顿描述观察苹果落地的过程并猜想其背后的原理时，“他说的是科学方法”。
“此外，苹果的形状让人想到地球，它是圆的，当然从树上掉下的苹果的确会让人想起亚当和夏娃的故事，信奉宗教的牛顿自然觉得这很合理。”
苹果落地事件发生于17世纪60年代中期，当时由于瘟疫的爆发使得牛顿就读的剑桥大学停课，牛顿只好回到他在英格兰北部的家中。
斯蒂克利的手稿讲述了1726年春天的一个下午，这位著名的科学家坐在“几棵苹果树的绿荫下”一边喝茶，一边与他分享了这个故事。
斯蒂克利在手稿中写道，牛顿告诉他，自己也是坐在苹果树下，灵机一闪，产生了万有引力的想法。
“当时他正坐在苹果树下思考问题，突然一只苹果从树上掉下，让他产生了这一想法。他心想，为什么苹果总是垂直落到地面？为什么它不向旁边落下，或是向上，而总是落到正中央的位置？”斯蒂克利写道，“这一定是因为地球在吸引它。一定存在着某种吸引力。”
除斯蒂克利的这篇手稿外，皇家学会网站上还登载了17世纪牛顿的学术对手罗伯特•胡克的一些科学记录，这些资料已失踪数百年，前不久在英国的一所房子里找到。
Vocabulary:
cursive:Having the successive letters joined together: 草书的：连续的字母连在一起的
hark back to: to remind you of, or to be like, something in the past 使想起
retreat: to escape to a place that is quieter or safer 隐退
perpendicularly: in a perpendicular manner 垂直地