MODERN SOIL SCIENCE—KELLOGG 239 
realization that experience on one soil, in one landscape, could not be 
relied upon where another soil was involved. Migrations were often 
disastrous for this reason. Then, too, world history records changes 
in the landscape under the very feet of the farmer, like the slow spread 
of the Sahara Desert as it gradually expands to its former position, 
following the moist period of glacial times (8). 
Unfortunately, the early scientists of Greece and Rome reached 
little into the problems of agriculture. With a few conspicuous excep- 
tions, the philosophers of that day accepted farming as the job of 
slaves, beneath the dignity of trained scholarship. 
THE GREAT DISCOVERIES 
The tempo of man’s struggle with his environment completely 
changed with two great forces: the rise of modern science and the great 
discoveries. The most important fact of Western culture was the 
opening of new land in the world. The forces leading to the pessi- 
mism of Malthus were already destroyed before his famous essay on 
population had been printed. Science began to increase productive 
efficiency. Western Europeans found new homes in the landscapes 
of the Americas. 
Europe had been bound by an aristocracy based upon land. Al- 
though many came to the new world to seek gold and adventure, 
most people came to find land and to build homes on the only security 
they knew. Gradually the east coasts of the new world filled up. In 
the beginning people were confined to land near the sea and to navi- 
gable waters, as they had been in the centuries before. But modern 
science came to the aid of discovery. The European colonists pushed 
into the interior, especially in North America. Railroads had made 
possible the exploitation of interiors of continents, of the great areas 
of black soils. Except for a few isolated spots, these soils were scarcely 
used by civilized folks at the time of the Treaty of Westphalia when 
modern nationalism had its birth. During the nineteenth century 
the black soils (Chernozem and Prairie soils) and the brown soils 
(Chestnut and Brown soils) in North America were occupied. The 
frustrated, the persecuted, the seekers of new opportunity had a place 
to go, and it was a good place with good soil. For over 200 years a 
man and woman could carve themselves out a farm home on the colo- 
nial frontier, in the Ohio Valley, on the great prairies of Illinois and 
Iowa, and finally on the Great Plains to the west. Grassland needed 
only cultivation, once transportation was established. 
In addition to the fine soils, there were other free resources, the 
forests and minerals. There was land in North America, Central 
America, South America, New Zealand, and Australia. Following 
the great discoveries Europeans found opportunities throughout the 
