It contains notable records of three distinct Eras in geological history.
"The Panjab, North-West Frontier Province, and Kashmir"
Sir James McCrone Douie
Here the whole history is divided into three distinct heads, or Eras,-the first branch of an analytical table of the whole story, from one or other of which all the other particulars, of whatever kind, must of necessity take their rise, and branch off in their natural order.
"A Practical Enquiry into the Philosophy of Education"
James Gall
Although it was one of the most distressing Eras in the Protestant Church, it gave birth to some of its grandest hymns.
"The Story of Our Hymns"
Ernest Edwin Ryden