Page:Popular Science Monthly Volume 23.djvu/439

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Higher Professional Aims.—"The Higher Professional Life" was the subject of Dr. J. M. Da Costa's recent valedictory address to the graduating class of Jefferson Medical College, Philadelphia. The higher aim of the physician should be to add to knowledge and increase the resources of his profession. It may be sought in various ways: by making original inquiries in the way that Darwin and Pasteur have so brightly illuminated; by cultivating literary tastes, and thereby becoming quicker in perception and more skillful in disseminating truths once learned; by mixing in the great movements that are to benefit mankind, and becoming influential in them; and by becoming active for the advancement of sanitative and preventive medicine. "There are thus many ways in which the aspirations of a higher professional life may be realized in useful or in great work. Some of these can be followed only when success has brought comparative leisure; but all can be kept in mind; one or all can be aimed at throughout our careers, and according to our individual strength."

The Glacial Moraine in Pennsylvania.—We have already mentioned the fact that Professor H. Carvill Lewis has traced the great glacial terminal moraine along its whole course through Pennsylvania. An account of his investigations is given in a paper recently read by him before the Franklin Institute of Philadelphia. The moraine enters the State in Northampton County, at latitude 40° 49′, and may be followed in a northwesterly direction till it enters New York from Potter County, at a height of 2,580 feet. It afterward turns at right angles to its former course, and, trending to the southwest, re-enters Pennsylvania at Pine Grove township, Warren County, whence it may be traced till it crosses the State line into Ohio at Darlington township, Beaver County, latitude 40° 50′. It thus leaves Pennsylvania at almost precisely the latitude at which it entered it; and, if a straight line were drawn across the State between these two points, the line of the moraine would form with it a right-angled triangle, whose apex would be a hundred miles distant from its base. The moraine crosses the Delaware at an elevation of 250 feet, the Allegheny River at an elevation of 1,425 feet, and the Beaver at an elevation of 800 feet above the sea, or 225 feet above Lake Erie. Upon the highlands it rises a thousand feet or more higher. The distinction between the glaciated portion of the State and the region south of glacial action is very marked, and the moraine itself is so sharply defined that at one point, Buck Mountain in Luzerne County, Professor Lewis was able to stand with one foot upon the glaciated and the other upon the non-glaciated region. The moraine is very finely developed west of Bangor, in Northumberland County, where it forms a series of "hummocky" hills one or two hundred feet high. Its course in Monroe County, as it winds from the top of the Kittatinny Mountain down to Cherry Valley, and then up again on to the Pocono, is a complete vindication of the glacial hypothesis. It is in no sense a water-level, nor could it have been formed by floating ice or by any other cause than that of a great glacier. It is wonderfully shown upon the summit of Pocono Mountain, over 2,000 feet above the sea, where a great ridge of moraine hills, twelve miles long, one mile wide, and 100 feet or more high, composed of unstratified till, and bearing numerous bowlders of Adirondack gneisses and granites, rises out of the plateau. The "kames" of Cherry Valley, with their accompanying "kettle-holes," and the terraces near Stroudsburg are also interesting features. Immense as was the power of the slowly moving glacier, says Professor Lewis, "it had but slight effect upon the topography of the country. It is a mistake to suppose that glaciers can level down mountains or scoop out cañons. The glacier had merely 'sand-papered' the surface of the rocks."

Joseph Duncan Putnam.—Joseph Duncan Putnam, late President of the Davenport (Iowa) Academy of Natural Sciences) who died December 10, 1881, had accomplished a remarkable amount of scientific work during his short life of twenty-seven years. He was born in Jacksonville, Illinois, in 1855; began making a collection of insects when eleven years old, and