The Saint Paul globe. (St. Paul, Minn.) 1896-1905, 1903-01-02
.FEATS OF Engineering
PLANS ARE MADE TO BRIDGE
THE RIO GRANDE
The Great Cut -oH That Is to Lead
Southern Pacific Tracks Across Salt
Lake-A Chasm Twice as Deep as
Niagara's to Be Slammed by Net
work of Steel.

q
SAN FRANCISCO, Cal, Jan. Il
Two remarkable engineering featS, both
associated with railroad extension, are
now in process of accomplishment on
this side of the Atlantic. One is the
Southern Pacific cutoff across the
Great Salt lake Of Utah. from ogden to
Lucin. The other is the lofty bridge
spanning the gorge of the Rio Grande
on the line of the Pacific railway of
Costa RIGA. Both undertakings are
attracting the attention of railroad en-
| gineers in Europe, as we'll as in all
parts of the United States. The pres
ent route of the Southern Pacific in
cludeS a stretch of 145 miles of track
! between Ogden and Lucin, which trav-
! erseS the northern shore of the Great
Salt lake for distance of fifty miles,
afterward turning to the west. An
unnecessary detour and several extra
| ordinarily heavy grades are the chief
disadvantages of this route. The cut
off viii do away with this detour and
with all of the troublesome grades. 1t
will extend westerly from Ogden to the
shore of the lake, thence crossing to
PrOmOntOry Point, on an embankment
| and trestle. and traversing the point
itself through a fve-mile cut of con-
| siderable depth until the main body
Of the lake is reached. The cutoff
then passes across the shallow water to
StrOng's Knob, whence it is continued
to Lucin. The total length of the new
line will be little over 102 miles, and
beside possessing the easiest of gradi-
ents, it will shorten the distance be-
tween Ogden and Lucin about forty
five miles. The cutoff covers an eight
mile stretch of water from the lake
shore to Promontory Point and an
other twenty-mile stretch from Pro-
| montory Point to Strong's Knob.
Z. w. Arthur. civil engineer who is
familiar with the construction work on
the cutoff, discussed the subject at
some length in a recent issue of the
Engineering News. Mr.. Arthur ex-
plains that as more than two miles of
the survey between the lake shore and
Promontory Point lay along bed of
mud some ten feet in depth it was
necessary to build a construction track
by placing three layers of sand bags,
which, in turn, rested upon long lines
of planking. This Instruction track
ran, of course, parallel to the perma-
nent track and was used for the car
riage of the shale and gravel that
formed the regular Toadbed.
Another very difficult engineering
problem concerned the fresh water
question. When the work began most
of the supply required had to be trans
ported from Ogden, infrequently an ex-
asperating delay. So, in order to pro-
vide substantial supply of good wa
ter, the engineers were obliged to bore
two artesian wells, one away out in the
lake and the other a couple of miles
inland. The supply from the lake we'll
has remained uniformly. pure and gen.
erous, while the land well has been
abandoned, owing to the constantly in
| creasing infusion of sand
Of the work of pile driving Mr.. Ar
thur has much to say that is of inter-
est. The differences in the lake bottom
are responsible for some curious hap
peningS. Sometimes blow of the
| hammer would drive the pile in no
more than a couple of inches; again it
would descend ten or twelve feet. Oc-
casionally hard strata were reached,
through which it was exceedingly diff
! cult to penetrate. In speaking of the
work on one section Mr.. Arthur says:
THE first pile, twenty-six feet long,
was driven out of sight by one blow of
the hammer. The second, twenty eight
feet long, was set upon the first and a
second blow sent both out of sight
The formation at this point is of mud
deposited by the Bear river, which
! flows into the lake from the north.
! Upon examination it was found that
mud to the depth of fifty feet had ac-
| cumulated. To cope with this 'out-of-
| sight pile driving, two forty foot piles
| were driven, tied, capped and braced
and when the rails are laid it is
| thought they will be strong enough to
| hold the construction trains while
| dumping their loads of fill, and in time
| the whole structure will become solid"
| The completion of the great cutoff is
set for January, 1904, although it may
| be postponed to a later date if the
character of the bottom in one portion
of the lake varies materially from the
| expectations formed of it by the engi-
| neerS.
The Pacific railroad of Costa RIGA
will be sixty miles long when finished
and will connect San Jose, the capital
of the republic, with the coast, passing
through the most fertile and populous
| districts. 1t will cost about So, 00O, 900
of our money, and of this large part
will be required to pay for the great
bridge over the Rio Grande. This
| bridge is to be 500 feet long, with rails
not less than $40 feet above the water
Just think of it, the canyon of the Rio
| Grande at this point is more than twice
as deep as the gorge at Niagara! The
bridge is designed by New York en-
| gineer, who has had extensive expert
| ence in this sort of work.