Rensselaer Journal, Volume 10, Number 47, Rensselaer, Jasper County, 2 May 1901 — Reproduces Geological Phenomena. [ARTICLE]

Reproduces Geological Phenomena.

Nothing could better illustrate the difference between old and new methods of getting at things than the interesting object-lesson work that is being conducted by Dr. T. A. Jagger in the Harvard geological laboratory. Here by a series of ingenious operations much like what a child would regard as play, the effects of the forces of nature are Illustrated in miniature. One piece of apparatus has been devised to explain the “ripple marks” seen in many fossils. These marks, it is found, are not caused by the direct swash of the surface of the waves, but by the oscillation of the deeper water. Plates of glass covered with sand are let down under water and subjected to different sorts of vibration, and ripple marks similar to the various types found in fossil forms are readily made. The effect produced by lateral pressure on stratified rocks is illustrated with layers of different colored wax, and miniature volcanic action such as that which formed the peculiar Black Hills of South Dakota is shown by forcing melted wax through layers of coal dust, plaster of paris, etc. The effects of erosion are shown by letting a fine spray of water fall on a miniature formation of land illustrating a variety of natural features. Geysers on a small scale are made and caused to spout with rythmical regularity like the ones in nature. Sand deltas left by the melting of glaciers are also reproduced, and in the same way many other phenomena hitherto explained only theoretically are demonstrated under the actual physical conditions reduced to a small scale in point of expanse and time.