UNDER THE APPLE-TREES 
watched over by some expert in the business, — 
which is, indeed, the case. This expert is water. Was 
there ever such a sorter and sifter? See the vast 
clay-banks, as uniform in quality and texture as a 
snow-bank, slowly built up in the privacy of deep, 
still rivers or lakes during hundreds or thousands 
of years, implying a kind of secrecy and seclusion 
of nature. Mountains of granite have been ground 
down or disintegrated, and the clay washed out and 
carried in suspension by the currents, till it was 
impounded in some lake or basin, and then slowly 
dropped. The great clay-banks and sand-banks of 
the Hudson River Valley doubtless date from the 
primary rocks of the Adirondack region. Much of 
the quartz sand isstill in the soil of that region, and 
much of it is piled up along the river-banks, but 
most of the clay has gone downstream and been 
finally deposited in the great river terraces that are 
now being uncovered and worked by the brickmak- 
ers. The sand and the clay rarely get mixed; the 
great hydraulic machine turns out a pretty pure pro- 
duct. The occasional mingling of sand and gravel 
shows that at times the workmen nodded, but the 
wonder is that, on the whole, the two should be so 
thoroughly separated, and so carefully deposited, 
each by itself. Flowing water drops its coarser ma- 
terial first, the sand next, and the mud and silt 
last. Hence the coarser-grained rocks and conglom- 
erates are built up in shallow water near shore, the 
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