万物简史 第90期:敲石头的人们(15)
Because the British were the most active in the early years, British names are predominant in the geological lexicon. Devonian is of course from the English county of Devon. Cambrian comes from the Roman name for Wales, while Ordovician and Silurian
万物简史 第91期:敲石头的人们(16)
Lyell, in his Principles, introduced additional units known as epochs or series to cover the period since the age of the dinosaurs, among them Pleistocene (most recent), Pliocene (more recent), Miocene (moderately recent), and the rather endearingly
万物简史 第92期:敲石头的人们(17)
Then come Lyell's epochsthe Pleistocene, Miocene, and so onwhich apply only to the most recent (but paleontologically busy) sixty-five million years, and finally we have a mass of finer subdivisions known as stages or ages. Most of these are named, n
万物简史 第93期:敲石头的人们(18)
Moreover, all this applies only to units of time . Rocks are divided into quite separate units known as systems, series, and stages. A distinction is also made between late and early (referring to time) and upper and lower (referring to layers of roc
万物简史 第94期:敲石头的人们(19)
Although there was no reliable way of dating periods, there was no shortage of people willing to try. The most well known early attempt was in 1650 when Archbishop James Ussher of the Church of Ireland made a careful study of the Bible and other hist
万物简史 第95期:敲石头的人们(20)
One of the better early attempts at dating the planet came from the ever-reliable Edmond Halley, who in 1715 suggested that if you divided the total amount of salt in the world's seas by the amount added each year, you would get the number of years t
万物简史 第96期:敲石头的人们(21)
By the middle of the nineteenth century most learned people thought the Earth was at least a few million years old, perhaps even some tens of millions of years old, but probably not more than that. So it came as a surprise when, in 1859 in On the Ori
万物简史 第97期:敲石头的人们(22)
Unfortunately for Darwin, and for progress, the question came to the attention of the great Lord Kelvin (who, though indubitably great, was then still just plain William Thomson; he wouldn't be elevated to the peerage until 1892, when he was sixty-ei
万物简史 第98期:敲石头的人们(23)
In the course of a long career (he lived till 1907 and the age of eighty-three), he wrote 661 papers, accumulated 69 patents (from which he grew abundantly wealthy), and gained renown in nearly every branch of the physical sciences. 在漫长的生涯里
万物简史 第99期:敲石头的人们(24)
He had really only one flaw and that was an inability to calculate the correct age of the Earth. The question occupied much of the second half of his career, but he never came anywhere near getting it right. His first effort, in 1862 for an article i
万物简史 第100期:势不两立的科学(1)
6 SCIENCE RED IN TOOTH AND CLAW 第六章 势不两立的科学 IN 1787, SOMEONE in New Jerseyexactly who now seems to be forgottenfound an enormous thighbone sticking out of a stream bank at a place called Woodbury Creek. The bone clearly didn't bel
万物简史 第101期:势不两立的科学(2)
That the bone didn't attract greater interest is more than a little puzzling, for its appearance came at a time when America was in a froth of excitement about the remains of large, ancient animals. The cause of this froth was a strange assertion by
万物简史 第102期:势不两立的科学(3)
Not surprisingly, such aspersions were indignantly met in America. Thomas Jefferson incorporated a furious (and, unless the context is understood, quite bewildering) rebuttal in his Notes on the State of Virginia, and induced his New Hampshire friend
万物简史 第103期:势不两立的科学(4)
In their keenness to demonstrate the incognitum's bulk and ferocity, the American naturalists appear to have become slightly carried away. They overestimated its size by a factor of six and gave it frightening claws, which in fact came from a Megalon
万物简史 第104期:势不两立的科学(5)
Inspired by the controversy, in 1796 Cuvier wrote a landmark paper, Note on the Species of Living and Fossil Elephants, in which he put forward for the first time a formal theory of extinctions. His belief was that from time to time the Earth experie
