abandoned. This was done on November 11th, 1908. Fig. 3, Plate L, shows the
finishing of the excavation on the north side of the work. On August 30th,
1908, a cut was made under Ninth Avenue at sub-grade, and cars could then
be run from Seventh to Tenth Avenue at sub-grade. On October 24th, 1908,
the connection with the disposal trestle east of Ninth Avenue was
abandoned, and all excavated material was hoisted from sub-grade at Tenth
Avenue by derricks.

As previously stated, the contractor was required to make complete disposal
of all excavated material after January 1st, 1909, but was allowed the use
of the pier until January 20th, 1909, after which date the materials were
hoisted by derricks at Tenth Avenue, loaded on 2-horse trucks, and
transported to the 30th Street pier, North River, where it was loaded on
scows by two electric derricks. A considerable amount of the rock
excavation was broken up and used for back-fill.

_Earth Excavation._--Practically all the earth excavation, amounting to
about 57,000 cu, yd., was done with steam shovels. The average quantity of
earth excavated by a steam shovel per 10-hour shift was 180 cu. yd. This
material was loaded on side-dump cars and taken to the disposal pier where
it was dumped through chutes to the decks of scows. Inasmuch as the
quantity of earth excavation was small, as compared with the rock, the
earth was used principally for the first layer on the scows for padding, so
that small stones might be dumped through the chutes without injuring the
decks.

_Rock Excavation._--As previously stated, the rock broke better on the
south than on the north side, where there were several slides, and
considerable excavation had to be taken out beyond the neat line required
in the specifications. The worst slide occurred at midnight on July 3d,