Basin and Range (Annals of the Former World Book 1)

by John McPhee

It was an angular unconformity in Scotland—exposed in a riverbank at Jedburgh, near the border, exposed as well in a wave-scoured headland where the Lammermuir Hills intersect the North Sea—that helped to bring the history of the earth, as people had understood it, out of theological metaphor and into the perspectives of actual time. This happened toward the end of the eighteenth century, signalling a revolution that would be quieter, slower, and of another order than the ones that were contemporary in America and France. According to conventional wisdom at the time, the earth was between five thousand and six thousand years old. An Irish archbishop (James Ussher), counting generations in his favorite book, figured this out in the century before. Ussher actually dated the earth, saying that it was created in 4004 B.C. The Irish, as any Oxbridge don would know, are imprecise, and shortly after the publication of Ussher’s Annales Veteris et Novi Testamenti the Vice-Chancellor of Cambridge University bestirred himself to refine the calculations. He confirmed the year. The Holy Trinity had indeed created the earth in 4004 B.C.—and they had done so, reported the Vice-Chancellor, on October 26th, at 9 A.M. His name was Lightfoot. Geologists today will give parties on the twenty-sixth of October. Some of these parties begin on the twenty-fifth and end at nine in the morning. It was also conventional wisdom toward the end of the eighteenth century that sedimentary rock had been la...