The following notes and observations are given in connection with the
skin friction and the bearing value of piles:

The writer has in his possession a copy of an official print which was
recently furnished to bidders in connection with the foundation for a
large public building in New York City. The experiments were made on
good sand at a depth of approximately 43 ft. below water and 47 ft.
below an adjacent excavation. In this instance a 16-in. pipe was sunk to
the depth stated, cleaned out, and a 14-in. piston connected to a 10-in.
pipe was inserted and the ground at the bottom of the 16-in. pipe
subjected to a loading approximating 28 tons per sq. ft. After an
initial settlement of nearly 3 in., there was no further settlement over
an extended period, although the load of 28 tons per sq. ft. was
continued.

In connection with some recent underpinning work, 14-in. hollow
cylindrical piles 6 ft. long were sunk to a depth of 6 ft. with an
ordinary hand-hammer, being excavated as driven. These piles were then
filled with concrete and subjected to a loading in some cases
approximating 60 tons. After a settlement ranging from 9 to 13 in., no
further settlement took place, although the loading was maintained for a
considerable period.

In connection with some other pile work, the writer has seen a 10-in.
pipe, 3/8 in. thick, 4 ft. below the bottom of an open cylinder, at a
depth of about 20 ft., sustain in gravel and sand a load approximating
50 tons when cleaned out to within 2 ft. of the bottom.

He has seen other cylindrical piles with a bearing ring of not more than