The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1870-01-27
A PRODIGIOUs PROJECT r,
Al Proposed Railroad Tunnel Under Lake
Michisan-Price,9 q OD, 1914, ,52S.
A Milwaukee, rnafhamaftcal Ves1iua naar de-

n NhWhhhOS AuhttOuhtiChW BCuiub nbS AS-
monstrated the cost and the entire pry.cticaoiity
of a tunnel under Lake Michigan, thus giving it
a railway connection with the Michigan shore,
and the result of his calculations is given in
article published in the Miwaukee Wisconsin.
1t is not without interest, and we append ex-
tract;--
'The actual surveys made shCw that the dis
tance across Lake Michigan is eghty-6ye miles
from beacon to beacon. To this at least one
from Milwaukee to Grand Haven eighty-six
miles, longer distance than 1t WAS ever at
tempted to tunnel before.
while the average depth of Lake Michigan
is 900 feet, the greatest depth between the two
points is IS fathoms, or 450 feet while the aver
age depth Is considerably less. 1t has been
deemed necessary by the engineers TO reach this
latter depth for greater security of the work.
Eighteen miles from the Milwaukee shore the
surveyors found a ledge of solid limestone four
miles wide over which there is 40 feet of water.
Aside from this ledge the survey found that the
earth to be gone through was of sand and gravel
which can be easily dug out. The shallowness of
the water between the two points, in compare
son with that of the lake generally, would indi-
cate, as was remarked by one of the surveying
party, that nature designed, whenever tunnel
should be built under Lake Michigan, 1t should
be here.
''Of course the work could never be accom-
plished by working at both ends, but il will be
necessary to carry the excavating along the en-
tire length at the same time. This will be done
by sinking large wrought iron tubes or cribs, at
a distance of one mile apart the entire distance.
These will be sunk down to the line of the tunnel
bed. the water pumped out and from these cribs
the workmen will work eastward and westward
until the gangs meet and the great tunnel is com
pleted Work can be kept up In this way night
and day. by change of gangs, and after the work
is completed, If the General Government see fit,
lights can be placed on these cribs, and they
perform duty as beacons to guide the weary sea-
farinU his Thpan prihc will aid
materially IN furnishing air to the tunnel, and
stationary engines Will be placed on each one for
that purpose. The engineers estimate shows
that six 10-horse power engines will be sufficient
to furnish electric light giving the entire tunnel
the brilliancy of daylight at all times.
"The cross section of the tunnel requires an
excavation of 25 cubic yards for every foot of
length. Not to trifle with fractions, there are
132, 600 cubic yards to be removed in every mile
of tunnelng, or grand total of II, ,352 600 yards
TO be taken ont to make the tunnel of sufficient
size to lay double track through it. This will
cost S3 per yard, making an aggregate of
.'There are also 51264o cubic yards of granite
to be excayated, which, at SIS per yard, would
be an aggregate of $41ol, 100. The tunnel is
to be faced up with brick, and of these il will
lay them, $50 per 1000 is the estimate made
giving an aggregate of S51, $40, 900. The ap-
proaches to the tunnel will cost at a rough esti-
mate $4,0o0,000. The iron cribs, SO being
ncCGESHTy lOT LuG WOTh, Will COSI PDU,UuO tdCN
making an aggregate of "a, 100000.
''Undor the head of general items for the work
we have steam engines, of which quite a number
will be necessary, dredging machines, scows,
salaries, iron TOOLS etc., at cost of $11 42 52S.
TO sum up these items, we have greHaCl
Excavating earth h..................$ .$34, o55, 600
Excayating stone. ne.................... 4,lOl, 600
Brick and laying. 'rr,.,-,.....'... 5l,Sdo'oo0 00
Approaches. .... -. ........,...... 4,OoO,0O0
So cribs at $4,000. 0................. 100000
General Items. ll,4SI,O
Total cost of tunnel ........ $lO9, 524, 52s
'We are satisfied that contingent expenses
resulting from breaks, overfows, ETC., would
not swell the amount to more that $115, ,00O, 900,
and what is this sum to Milwaukee, in compari.
son with the benefits that would result? Our
members Of Congress win be requested to press
the matter at the present session; and We hope
that an early day In the spring of 1870 the first
will take, it is thought fully two years and four
months to complete it, 30 that the first train