48 



had only a small load a shallow soil was left. Again, if the ice front 

 remained for a long time near a certain place, as near your home, it 

 kept bringing and dumping rock fragments to form moraines, which, 

 of course, would continue to grow higher so long as the ice dumped 

 it, much as a sand pile will continue to grow higher so long as fresh 

 loads are brought and dumped. 



There are other causes for difference in the glacial soils, but most 

 of them cannot be considered here. One of them is so important, 

 however, that it must be mentioned. With the melting of so much 

 ice, vast floods of water were caused, and these came from the ice, 

 perhaps in places where there are now no streatns, or at best small 

 ones. These rapid currents carried off much of the rock flour and 

 left the coarser and heavier sand, gravel, or pebbles, the latter often 

 well rounded, with the scratches removed by the long-continued 

 rolling about in the glacial stream bed. 



One ofter flnds such beds of sand or gravel in different parts of 

 the State, telling not only of ice where it is now absent, but of water 

 currents where is now dry land. The rock flour was in some cases 

 carried to the sea, elsewhere to lakes, or in still other places deposited 

 in the flood-plains of the glacier-fed rivers. JN^ow some of this rock 

 flour is dug out to make into bricks. 



Enough has been said to show that the soils of New York were 

 brought by a glacier and to point out that there are many differences 

 in the thickness of the soil as well as in kind and condition. The 

 agriculture of the State is greatly influenced by these dift'erences. 

 In some cases one part of a farm has a deep, rich soil, another part 

 a barren, sandy, pebbly or boulder-covered soil (Fig. 14), while in 

 still another part the bed rock may be so near the surface that it 

 does not pay to clear it. Moreover, some farms are in hummocky 

 moraines, while others, near by, are on level plains (Fig. 27), where 

 a broad glacial stream built up a flood-plain in a place where now 

 the stream is so small that it never rises high enough to overflow 

 the plain. 



There are even other differences than these, and one who is familiar 

 with a region is often puzzled to explain them ; but they are all due 

 to the glacier or to the water furnished by its melting, and the care- 



440 



