Evening star. [volume] (Washington, D.C.) 1854-1972, 1918-04-21

smaller greyhounds of the Atlantic.
1 asked Mr.. Wig as to whether these
ships would not be very much heavier
than other vessels of the same size now
one the ocean. He replied that the weight
Of a vessel of reinforced concrete will
be from Is to 20 per cent heavier than
one of the same tonnage constructed
of steel. but that the cost Of the. con-
crete ship will be only two-thtrds or
three-fourths as much as that OF the
steel ships 1t will take as long or
longer to build the concrete ships as
steel ships. but the. plant for erecting
more quickly, and 1t will be much less
expensive. A steel shipbuilding plant
costs in the neighborhood of 100000.
and upward, whereas one for concrete
ships can be erected for $4,000 or less
Moreover" continued Mr.. Wig. 'tthe
materials used in making the concrete
feet are such that shApbuilding plants
can be erected almost anywhere along
our coast. All that we need is some
Portland cement. some steel rods and
gravel bank. or one might use clay
bank and kiln and make terra Gotta. in
stead of stone. They are now using
crushed terra Gotta in the concrete yes
sells being built in San Francisco. The
terra Gotta if properly burned becomes
as strong as the stone when mixed with
cement. 1t is full of pores and air
spaces. and consequently is much light
weight of the hull as far as possible
consistent with the strength of the
ship. 1t is estimated that for every
pound per cubic foot that we can cut
can reduce the weight of the ship from
ten to twenty tons. depeas4ng upon the
size of the vessel. If the Weight is re-
duced twenty pounds per cubic foot
the ship will carry from 200 to 400 tons
more of cargo. 1t is therefore impor-
tant that the concrete be made as light
in weight as is possible"
here asked as to the amount of steel
in the big ships. and was told that each
Of the larger vessels will have more
than $4,000 steel rods of the larger size
weighing $50 tons and an equal number
or more of steel rods ranging from one
half an inch upward in diamter. Each
of these rods is sixty feet long and II all
were Joined together they would make
oae great strand of steel so long that
1t would reach from Boston to New
York and thence on to Washington. The
larger steel rods are bigger around
than a hoe handle
Another advantage to the govern
ment in building concrete ships in this
time of great need" continued Mr..
Wig. "is that the work can be done
by p class of men which is not now
employed in war work. and by men
who cannot be used in the building of
ships of steel and wood. One of the
chief difficulties in our hurried ship
building construction just now is the
lack Of skilled labor. We cannot find
the skilled men. and 1t takes time to
crete construction brings in p. new class
of labor as well as of material. and
thereby adds one more factor to our
side of the equation in winning the
war;
Have concrete ships any advantage
over ships of steel and wood?" l asked.
They have some advantages and
some disadvantages" replied Mr.. Wig.
but the chief reason for the concrete
ship just now is that we need more
vessels to Withstand the submarine
at tho earliest possible moment"
Throughout our conversation about
concrete ships Mr.. Wig was very con-
sentative. He evidently believes that
pected IF them. but says that the gov
eminent expects to test them out
thoroughly before entering: into any
large shipbuilding program: Many of
being carefully studied, and expert
ments are made to remedy the Difficult
ties which arise. A very important
matter is the durability of the ship and
whether its life may not be heightened
Mr.. Wig thinks it can, and has judg--
ment or such matters is worthy NJ
great consideration. In connection with
the bureau of standards here at Wash
ington. he has been engaged for long
time investigating ali natter. rel...-
ing to concrete ard its durability. 1t
was not long ago that he was sent by
the Navy Department to inspect the
concrete construction along the At
lantic and Pacific coasts of this coun-
try and Canada. He also visited all
tho ports and examined the concrete
harbors of the West India Islands.
4 During this work he found that the
concrete was greatly affected by the
salt in sea water. a matter which Is
important in making these ships to
sail over the oceans He found that
wherever the concrete came In contact
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