Evening star. [volume] (Washington, D.C.) 1854-1972, 1904-07-02
engineers.
The Construction Equipment

unfamiliar with the work Of modern civil
engineers.
The Construction Equipment
The construction equipment consists Of q
steam shovel with a capacity of a cart load
at a single SCOOP two or three dummy en-
gines with an unlimited supply Of dirt carts
and three huge travellers" platform der
ricks. that are set on wheels so that they
can be moved forward as conveniently as
a railroad train. Each of these travellers
has two engines and two derricks. the
arms of which can swing over the edges of
the tunnel cut to the street level where
the granite for the construction Is kept.
"A concrete machine completes the equip
ment for the work. This machine is placed
on the side of the cut and concrete is
manufa ctured In it as fast as the materials
can be supplied. The process by which the
work is done is as simple as the material
for the building is profuse. The steam
shovel leads the procession, tracks being
laid for ii ten feet at a time. 1t digs out
the trench in huge scoopfuls 4 cubic yard
at a time. The trench is almost the width
of the street from curb to Grub Men are
then set to work digging smaller trenches
along the side of the tunnel in which the
concrete foundations for the walls is laid.
The walls themselves are put up as soon as
the foundations have hardened or set
the travellers furnishing the masons with
the material for their work fast as they
can use it. The earth that is dug from
the tunnel by the steam shovel Is hauled
through the cut by the dummy engine In
the dirt and is dumped on the COM
pleted work in the rear. Thus the dirt
that is being taken from the block between
Sd and 4th streets southeast is being dump
ed in the completed section between list and
I'd streets southeast.
The top Of the tunnel, except at the
street crossings, is open and the method
Of construction can be plainly seen. While
the cut looks very narrow, double track
will be laid along 1t and trains going In the
opposite direction can pass easily. The
track will be ballasted with concrete and
broken stone, it is understood. One Of the
features of the work that attracts much
attention is the little inches to be seen at
intervals of 100 feet along the completed
walls.
These inches are about seven feet in
height and two or three feet deep. They
are at opposite intervals on both sides of
the wall. that is, while they are one hum
dred feet apart Oh both sides, the inches In
the north wall are opposite points midway
between the inches in the south wall, SO
that there is niche in one wall or the other
every fifty feet of the tunnel This Is a most
important feature of the construction, as
| it would be impossible for section gang
to work at the tracks in the tunnel If it did
rot have place of some kind to climb into
when 4 train was passing.
The LIST street tunnel. the one which will
run to the union station, is well under way.
1t is explained by the engineers that this
tunnel is divided into two sections The
cut for the first. called the open work. Is
almost completed. and the second, the driven
work, has not yet been begun. The open
work is lie part of the construction which
is done in an open trench and the driven
work is the part which is to be driven by
preura tie power through Capitol Hill. The
open work tunnel forms the arc of an i'm
mense circle extending from South Capitol
and E streets to list and streets south