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NATURE AND ORIGIN OF TIIE LOE;

CHAP. XVI.

CHAPTER XVI.

NATURE, ORIGIN, AND AGE OF TIIE EUROPEAN LOESS.

NATURE, ORIGIN, AND AGE OF THE LOESS OF THE RHINE ANDDANUBE—IMPALPABLE MUD PRODUCED BY THE GRINDING ACTION OFGLACIERS—DISPERSION OF THIS MUD AT THE PERIOD OF TIIE RETREATOF THE GREAT ALPINE GLACIERS—CONTINUITY OF THE LOESS FROMSWITZERLAND TO THE LOW COUNTRIES—CHARACTERISTIC ORGANICREMAINS NOT LACUSTRINE—ALPINE GRAVEL IN THE VALLEY OF THERHINE COVERED BY LOESS—GEOGRAPHICAL DISTRIBUTION OF THELOESS AND ITS HEIGHT ABOVE THE SEA—FOSSIL MAMMALIA—LOESS OFTHE DANUBE—HIMALAYAN MUD OF THE PLAINS OF THE GANGES COM-PARED TO EUROPEAN LOESS—OSCILLATIONS IN THE LEVEL OF THE ALPSAND LOWER COUNTRY REQUIRED TO EXPLAIN THE FORMATION AND DENU-DATION OF THE LOESS —MORE RAPID MOVEMENT OF THE INLAND COUNTRY.

Nature and Origin of the Loess.

I NTIMATELY connected with the subjects treated of inthe last chapter, is the nature, origin, and age of cer-tain loamy deposits, commonly called loess, which form amarked feature in the superficial formations of the basins ofthe Rhine , Danube , and some other large rivers draining theAlps, and which extend down the Rhine into the LowCountries, and were once perhaps continuous with others oflike composition in the north of France .

Some skilful geologists, peculiarly -well acquainted withthe physical geography of Europe , have styled the loessthe most difficult geological problem, although belongingto the period of existing land-shells, and the highestand newest by position of all the great formations ; andin a work dealing with the evidences of the antiquity ofman, I the more willingly devote a chapter to this Alpine