Page:Popular Science Monthly Volume 55.djvu/126

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POPULAR SCIENCE MONTHLY.

of Pengelly's geological investigations previous to his engaging in systematic cave exploration. They embraced fields chiefly in Devonshire and Cornwall, and afforded subjects for correspondence and discussion with many of the most eminent British geologists, and some of other countries than England. A study of some fossil fish, first observed by Mr. Charles W. Peach in Cornwall, furnished the occasion for one of his first recorded papers, On the Ichthyolites of East Cornwall, in the Transactions of the Royal Geological Society of East Cornwall, 1849-'50; and a single volume—the seventh—of these Transactions contains nine of his papers. Another subject of interest was the beekites, curious formations of chalcedonic silica on the limestone fragments in the New Red Sandstone of Devonshire, first observed by Dr. Beek, of Bristol, concerning which he read a paper at the Cheltenham meeting of the British Association, the first which he attended, in 1856. In 1860 he completed the formation of a collection of Devonian fossils from Devon and Cornwall, which was presented by the Baroness Burdett-Coutts to the new museum of the University of Oxford, in connection with the foundation of a geological scholarship, and was named "the Pengelly Collection."

The first of the more important geological researches with which Pengelly's name is intimately associated was the exploration of the peculiar formation at Bovey Tracey, for the identification of its fossils and the determination of its age. The plain in which the formation lay had an aspect suggesting the basin of an ancient lake, and its deposits, "very different from the solid rocks of the surrounding hills," confirmed the suggestion. They consisted of gravels, sands, and clays, distinctly stratified, with seams of lignite, for which they had been worked. The pits had already attracted some notice, and the deposits had been mentioned in scientific literature, but very little had been learned concerning their age. In 1860 the subject was mentioned by the late Dr. Falconer, an eminent paleontologist, to Miss Burdett-Coutts as one the investigation of which would be a boon to science. Miss Coutts supplied the money that was needed, and the direction of the systematic investigation was intrusted to Pengelly; on learning which, Sir Charles Lyell wrote to him: "I am very glad of the prospect of our knowing something of the Bovey coal plants. It is almost a reproach to English geology that they have been so little explored, as they are perhaps the only fossils of the Tertiary period to which they belong." In order to determine accurately the nature, thickness, and order of the successive beds, and to make a satisfactory collection of fossils, a new section of the deposit was made, measuring one hundred and twenty-five feet, down to the bottom of a seam of lignite four feet in thickness, the "last bed" of the workmen, but not at the actual base of the deposit.