牛頓密友手稿披露萬(wàn)有引力發(fā)現(xiàn)過(guò)程

It always falls down. That's how the apple helped Isaac Newton.

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.

它總是垂直下落——蘋(píng)果正是這樣啟發(fā)了艾薩克•牛頓。

本周一，一份有關(guān)牛頓是如何發(fā)現(xiàn)萬(wàn)有引力定律的18世紀(jì)的手稿被傳到網(wǎng)上，讓不易保存的紙質(zhì)手稿內(nèi)容首次在網(wǎng)上與公眾見(jiàn)面。

牛頓與蘋(píng)果的故事是最著名的科學(xué)軼事之一，現(xiàn)在這個(gè)故事竟可以在褪了色的手寫(xiě)稿中讀到，這份手稿的內(nèi)容是由與牛頓同時(shí)代的（科學(xué)家）威廉•斯蒂克利記錄的。

皇家學(xué)會(huì)圖書(shū)館館長(zhǎng)基斯•摩爾說(shuō)，蘋(píng)果落地的故事已經(jīng)流傳了幾個(gè)世紀(jì)，因?yàn)樗囊饬x十分重大——它不僅奠定了現(xiàn)代科學(xué)的根基，暗示了太陽(yáng)系的運(yùn)行原理，甚至還暗指了《圣經(jīng)》。

摩爾說(shuō)，當(dāng)牛頓描述觀察蘋(píng)果落地的過(guò)程并猜想其背后的原理時(shí)，“他說(shuō)的是科學(xué)方法”。

“此外，蘋(píng)果的形狀讓人想到地球，它是圓的，當(dāng)然從樹(shù)上掉下的蘋(píng)果的確會(huì)讓人想起亞當(dāng)和夏娃的故事，信奉宗教的牛頓自然覺(jué)得這很合理。”

蘋(píng)果落地事件發(fā)生于17世紀(jì)60年代中期，當(dāng)時(shí)由于瘟疫的爆發(fā)使得牛頓就讀的劍橋大學(xué)停課，牛頓只好回到他在英格蘭北部的家中。

斯蒂克利的手稿講述了1726年春天的一個(gè)下午，這位著名的科學(xué)家坐在“幾棵蘋(píng)果樹(shù)的綠蔭下”一邊喝茶，一邊與他分享了這個(gè)故事。

斯蒂克利在手稿中寫(xiě)道，牛頓告訴他，自己也是坐在蘋(píng)果樹(shù)下，靈機(jī)一閃，產(chǎn)生了萬(wàn)有引力的想法。

“當(dāng)時(shí)他正坐在蘋(píng)果樹(shù)下思考問(wèn)題，突然一只蘋(píng)果從樹(shù)上掉下，讓他產(chǎn)生了這一想法。他心想，為什么蘋(píng)果總是垂直落到地面？為什么它不向旁邊落下，或是向上，而總是落到正中央的位置？”斯蒂克利寫(xiě)道，“這一定是因?yàn)榈厍蛟谖?。一定存在著某種吸引力。”

除斯蒂克利的這篇手稿外，皇家學(xué)會(huì)網(wǎng)站上還登載了17世紀(jì)牛頓的學(xué)術(shù)對(duì)手羅伯特•胡克的一些科學(xué)記錄，這些資料已失蹤數(shù)百年，前不久在英國(guó)的一所房子里找到。