The record-union., 1899-03-20
MR.. KNAPP AND HIS BOAT.

Mr. Knapp, the inventor Of the roller
shpbuilding and engineer critics. He
invented q roller boat some years ago,
a boat that is simply long cylinder
with a row of moving fianges about the
central section taking the place of pad
dies. In spite of the opposition to his
ideas he built boat at Toronto and
recently gave it a trial. but succeeded
in making no more than six knots an
hour. which made it far from what he
had claimed for it.
Nevertheless, Knapp insists that as
water is practically incompressible, it
is easier to roll over it than to plow
through it. As he terms it, the water
becomes a granolithic pavement, so to
speak, under his boat and the latter by
its motion is lifted constantly toward
the water surface. He holds that as a
body can displace only its own weight
in water, as soon as resistance exceeds
the weight Of his vessel it must practi-
caEly roll on top Of the waves.
But the engineers have replied to this
that with such a vessel exposing
great broadside to the wind no speed
could be attained in gale. or against
a strong breeze. He replies to this
sharply, by saying that a great steam
ship like the Campania drawing SO feet
of water, or two-thirds her entire hight
is more irnpeded by the water than by
any gale, as the water strikes her with
all it's momentum, Ga pounds to the
cubic foot, the wave motion having a
speed Of, say, 20 feet per second. But
the wind strikes third Of her with a
pressure of but few pounds per foot.
Water, says Mr.. Knapp, is $50 times
heavier than air, and the Campania
necessarily goes through it at a re-
duced speed, but in the roller boat the
resistance of skin friction and the blow
of a wave which is much below the
center, knocking her legs from under
her. so to speak, are aids to speed.
Thus turn an enemy into friend,
and am working with nature instead Of
fighting her."
Thus he insists that the wind can no
more stop his boat weighing 1900 tons
and upward. according to load. than 1t
can railroad train. This Is adroit,
and 1T must be confessed ingenious rea-
soning. and it is to be said also that
q number of engineers and builders
agree with Mr.. Knapp. AS to his re-
cent trial it, is explained that the con-
ditions were, not bad, but that the trial
engines, and that his invention will op-
crate with satisfaction only where the
boat is of sufficient size to carry power
full motors.
SO Mr.. Knapp wishes the Government
to authorize him to build troopship
capable of carrying 10000 (?) men. 1t
would be 500 feet in length, 200 feet in
diameter, with eight decks of varying
to ceiling. There are to be 7S0 COM
partments 62 feet inches long, be-
tween thetintermediate and outer skins
of the boat, and 600 more between the
inner and intermediate skins, or walls,
of the boat
The engine compartment in the center
of the boat is to be 200 feet long by
16S feet in diameter, swinging on jour-
mails at either end, the cabins also
swinging in the same way, but inde-
pendently. In the bottom of the boat
would be the fuel tanks capable of
carrying sufficient fresh water for the
boilers. while the coal bunkers would
have a. capacity of 5000 tons.
OF course the Government has not ac-
cepted Mr.. Knapp's offer. 1t cannot
very Well engage in such experiments.
He must manage to demonstrate the
value Of his boat alone, or by and of
associated private capital He can
then, as the Literary Digest" face
tiously suggests. build his ships by the
dozen and set his price at what he
pleases. If they manage to beat the
Campania In speed. This is to be said,
however, that there is SUFFICIENT in
Knapp's idea Of roller boat to be
worthy: OF sincere examination, In this