New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1917-07-22
U-Boat Menace Would Be
Ended, Says N. Y. Inventor
of Boring Machine
Approved by Experts
Tubes Can Be Dug at Rate Of
100 Feet a Minute, 1t
Is Claimed

A plan for boring four tunnels be-
meath the English Channel within thir-
ty-fve days has been submitted TO the
British Cabinet by John K. Hencken,
O civil engineer, Of 500 Fifth Avenue,
who claims to have invented a machine
which will cut through earth and rock
at the rate of 100 feet an hour.
Mr.. Hencken asserts that he can
have the tunnels completed and ready
for operation within a few months
time. His plans not only provide for
a trackway in each tunnel, but drive
way as well, along which motor lorries
can be driven from England TO the
supply bases in France without break
ing bulk.
Turned Discussed for Years
The Dover Calais tunnel has been
discussed by the British and French
governments for many years. Just
prior to the war it was figured that
only two tunnels would cost between
$50 900 900 and s1o0, Oo0, 900. Under the
old methods 1t has been figured that II
would take approximately eight years
to complete the task which Mr..
Hencken claims he can accomplish
within few months time. At the
present high cost of labor and mate
rails the tunnels would cost in the
neighborhood Of 100000 900 under the
old methods. Mr.. Hencken gives no es-
timated cost, however, under his plans.
He claims TO have had the sanction
Of the United States government in
offering the plan to England. He offers
to finance the scheme by floating bond
issue, which could be paid off within
a few years time. and then to make
the tunnels a present to England and
France by the United States.
According TO Mr.. Hencken, his plan
has been under consideration by the
British government since last May,
when the English commission, headed
by Arthur James Bslfour, visited this
country. He produced letter yester-
from Mr.. Balfour's secretary acknowl-
edging the receipt Of the plans and an
nouncing that the plan was under con-
sideration by the British authorities.
He said the scheme has been brought
TO the attention of President Wilson
and Secretary Lansing and has the ap-
proval of such men as Brigadier Cen
eral William II. Bixby, U. s. A., re-
tired, former Chief of Engineers; K.
P. Clarkson, professor Of engineering
in Acadia University, Canada. and
Worthington NJ. Jacobus, consulting
engineer and secretary and treasurer
Of the New Jersey Ship Canal Com
mission.
In his offer to the British govern
ment Mr.. Hencken stated that the
work would be undertaken by Ameri-
can, British and French engineers. I'M
der the direction Of Colonel John Be-
CART, civil engineer, Of New York
and London.
Would Use Eight Machines
His plan is to have eight of his
machines in use, one at each end of
the four tunnels. and another set of
eight machines boring the approaches
at the same time. Two of the tunnels
would cut at depth Of 100 feet below
the channel bed "to avoid possibility
of injury from above" and the other
two somewhat lower ITO be used as
drainage tunnels additionally to their
use as traffic tunnels" The bores will
be cylindrical in shape, unless il is
decided to have both driveways and
trackways, in which case the lower
half will be cut square or rectangu-
lar.
Mr.. Hencken pointed to recent
statement by Professor Krueckmann,
OF Muensten, Germany, 10 the effect
that one of England's first acts after
the war would be "to construct the ia
nous tunnel from Dover to Calais,
which would make Germany's sub
marines valueless and place Germany
at the mercy of England in the second
war" Mr.. Hencken explained that
Professor Krueckmann deems a sec
ond war between England and Ger
many inevitable.
In describing his machine, Mr..
Hencken says it consists of a series
of swinging hammers rotated at a
peripheral speed of about 500 feet a
second. striking several hundred thou
sand blows a minute on the face TO be
excavated and pulverizing the mate
rails from FIVE inches in greatest di
mension down to impalpable powder"
Each blow, he says, would have the
force Of a 3-inch solid projectile. The
machine, with all appurtenances,, is
moved forward by system of cater
pillar tractors and the material is car
ried away on belt conveyers.