Isaac Newton masterwork becomes most expensive science book sold

First edition of Principia Mathematica, which was published in 1687 and sets out Newton's laws of motion, raises 3m at auction

A first edition of Sir Isaac Newton's Principia Mathematica has become the most expensive printed scientific book ever sold at auction after a winning bid of $3.7m (3m), the auction house Christie's has announced.

The edition of Newton's 1687 work, described by Albert Einstein as "perhaps the greatest intellectual stride that it has ever been granted to any man to make", went for nearly two and a half times its highest estimate.