The morning times., 1896-12-27
THE BOSTON SUBWAY.
New Plan to Relieve Travel in the
Congested District.


The great subway in Boston, which is to
carry the street cars underground through
the conEested district and to relieve the
intolerahle pressure upon street traffic, has
now been under construction for consider
ably more than year.
The Character.of the Work varies accord
ing 20 the radically varying conditions of
the different sections of the route, but in
teiruption To street traffic is reduced TO
minimum, and danger TO high buildings
through undermining their foundations is
entirely averted hy the adoption of Il very
simple and ingenious method, which has
been enthusiastically commended Dy ylsiu-
ing engineering authorities. Ii is here
practiced for the first time, having been
devised to meet the e2igencies of the stu
auon, ana is donbtless,tl destined to be used
in all cases where similar conditions exist
1t has been termed The Slice method OF
construction. At intervals along q given
section of the projee,'sd subway Trenches
about Nv welve feet wideare excavated across
the street OF distane and depth CORE
spending TO the size of the subway.
This excavation is briuged over flush with
the street pavement by strong beams aud
imbering. These beams are used TO sup
port the street railway tracks as well as
the ordinary traffic. The Width Of the ex-
cavaiion being Cnly twelve feet. the water
mains, gas pipes. etc, require but little
support, ana they are either left in place
or gradually removed TO new locations, as
circumstances may demand. In the same
way ali excavation SO narrow cannot en-
danger adjacent buildings 10 any appre-
ciable danger, but where IL extends very
near the buildings il is made as much mar
rover than twelve feet as practicable
BY this means a SIN all portion or slice
OF the subwayis completed in each trench
In due time each slice thus built is properly
Joined to the contiguous slices. The con-
tractor for a given section is REQUIRED to
nave at all times aS many trenches under
excavation, being.fillcd with masonry. and
belng back-flled with earth above COM
pleted masonry az is necessary for the
even and steady progress Of the work to-
ward completion at the time agreed upcn
The works. carried on by night aS wen as
by day, and in localities where street traf-
fic is great il is chiefly done at night The
earth is for the greater part removed bv
buckets carried upon endless cables sup
ported on scaffoldng constructed over the
SIDEWALKS at convenient places and thus
carried along TO points where it may be
received by carts without obstruction to
ordinary traffic.
10 laCiltate excavation the planking is
removed from these bridges in de grees vary
ing Vlth the amount Of streettraffic at diff.
erenthours ForinstanCe. .itiSprovide ed that
on fremont street betw cen a m and : a.
m. tWo-thirds OF the street shall be unob-
structed, and all tracks kept open for the
passage OF cars: from 7:30 p. IN. to | /: 80 d.
m, one-third the width of the street is to be
open. and at least Gne track; from IL 30 ~
m TO u a. III, nc tracks need be in service
ana for the next hour, until a. m. at
least one track must be open. In section of
The street 300 feet long not over l 90 feet
can be under construction at the same
Tune. There are also suit able regulations
Tor the convenience of sidewalk traffic.