ter's experience.
The writer believes that the foregoing notes will show conclusively that
the factor to be sought in pile work is bearing value rather than depth
or skin friction, and, however valuable skin friction may be in the
larger caissons, it cannot be depended on in the case of small piles,
except in values ranging from 25 to 100 lb. per sq. ft.
In conclusion, he desires to thank the following gentlemen, who have
contributed to the success of the experiments noted herein: Mr. James W.
Nelson, of Richard Dudgeon, New York; Mr. George Noble, of John Simmons
and Company, New York; and Mr. Pendleton, of Hindley and Pendleton,
Brooklyn, N.Y.; all of whom have furnished apparatus for the experiments
and have taken an interest in the results. And lastly, he desires
especially to thank Mr. F.L. Cranford, of the Cranford Company, for men
and material with which to make the experiments and without whose
co-operation it would have been impracticable for the writer to have
made them.
Throughout this paper the writer has endeavored, as far as possible, to
deduce from his observations and from the observations of others, as far
as he has been able to obtain them, practical data and formulas which
may be of use in establishing the relationship between the pressure,
resistance, and stability of earths; and, while he does not wish to
dictate the character of the discussion, he does ask that those who have
made observations of a similar character or who have available data,
will, as far as possible, contribute the same to this discussion. It is
only by such observations and experiments, and deductions therefrom,
that engineers may obtain a better knowledge of the handling of such
materials.
The writer believes that too much has been taken for granted in
connection with earth pressures and resistance; and that, far too often,
observations of the results of natural laws have been set down as
phenomena. He believes that, both in experimenting and observing, the
engineer will frequently find what is being looked for or expected and
will fail to see the obvious alternative. He may add that his own
experiments and observations may be criticized for the same reason, and
he asks, therefore, that all possible light be thrown on this subject. A
comparative study of much of our expert testimony or of the plans of
almost any of the structures designed in connection with their bearing
upon earth, or resistance to earth pressure, will
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