Page:Popular Science Monthly Volume 72.djvu/515

 The township contains no extensive areas of outcropping coal measure or Pennsylvanian formations, save in the south central portion; elsewhere disintegration has left only outliers. In the area west of Mary Ann Furnace, covering several square miles, and another along the eastern border of the township, there are eighteen houses, three of which, now occupied, have springs. For the entire township, the average number of houses per square mile is about eight; for the horizon of the coal measures, it is less than two. That springs are rare is not the sole cause for the discrepancy; the bleakness of the upland, and the unproductiveness of the soil are contributory factors.

About ten per cent. of the homes with springs are built on glacial deposits. The drift is localized chiefly in the valleys. The ice-sheet covered approximately two fifths of the township, but left scarcely a veneer of drift on the intervalley areas. While fourteen springs have been mapped as belonging to the drift, it is quite probable that a good fraction of these are fed by water courses from the Black Hand formation. Of the wells noted, fifty-six per cent. are in glacial deposits.

Still another evidence of the influence due to springs is seen in the fact that of the eight deserted houses in the township one is in the Black Hand formation, one in the Logan and six in the coal measures, the horizon practically without springs. It is noted also that twenty-two per cent. of the dwellings are off highways, an isolation due entirely to springs. Furthermore, dairying has always been carried on in this region because in the summer season the springs furnish cool water for handling milk.