The daily Cairo bulletin. (Cairo, Ill.) 1878-1???, 1883-11-10
The Daily Bulletin.
A VANISHING LEGEND.
That to the Effect That Two Boats Cannot
be Built to be Just Alike.

AIS il true, when Il fast steamer has
been brought out, that all attempts to
build her equal, even by following the
lines of her model, are failures?' was
asked of Mr. John Roach, the iron ship
builder.
''The Mary Powell is given as an in
stance of the kind" said he. There
are other cases where fast boats have
been built and other builders have tried
to initiate them without success, The
length and beam and the various di-
mansions are obtained, and the frames
are laid down on the floor accordingly,
but when the boat slides into the water
ii is found that they have quite differ
ent craft in speed, if not in other partic-
ulars. An imitation is never equal to
the original The truth is, the imitation
cannot be built on the lines of the origi-
nal boat. Builders do not tell the Sc
crets of their models to others. They
may hang up pretty model in the Of
fee, and label it with the name of the
fast boat. 1t is not the model of the
boat, however If boat is ordered at
one yard, to be exactly like some other
one built in that yard, an approxima-
ton can be obtained. If the old draw
ings are on hand they can be transfer
red to the floor and patterns made from
them, and the frames and beams will
be made from the patterns. But human
skill is not so perfect that it can make
piece of iron, thirty or forty feet long.
that will be exactly like piece that
was made a year or two years before.
Slight variations will be made in trans
ferr.ng the draft to the floor, in making
the patterns, and in bending the frames.
When an order is given for two or more
steamers to be built at once and exactly
alike, the problem is simpler. Within
year we have built six steamers, three
from one model and three from another.
They are the San Juan, San Jose and
San Bias, and the Finance, Advance
and Reliance. The Reliance, for in
stance, will be found to be exactly like
each of its sister ships, by any system
of measurement that can be devised.
There is difference in the time made
between ports by these vessels.
Handling a ship is a delicate matter
as well as building ship. Some allow
ance must be made for difference in the
skill of navigators and of engineer and
firemen. / can build ship and guar
antee any speed required within certain
limits, but must have her handled in
my way to attain the contract speed
Some men make fire two feet thick
Others take a pride in their business,
and keep thin fire that makes steam
half faster with less coal. Some navi-
gators know how to trim their cargo to
give their ships the highest speed But
with all those things equal there are
differences in ships which are apparent
ly just alike. The difference will usual
ly be found very slight. 1t could be
found if looked for,
Mr.. A. Perry Bliven, who has modelled
a number of fast yachts, was asked if
he thought that two ships built on the
same lines could have different speeds.
He said: Certainly; but it does not
follow that there is any mystery about
it. Iron ships can be built to run any
desired speed inside the limit, and the
limit is growing larger Many yachts,
especially, have been built on the same
model that were as far apart in speed
as clipper ships and Dutch galleyS. The
search for the difference did not always
reveal it. Apparently slight differences
in the sci of the sails, in the rake of tho
masts, in the trim of the ballast, in
weight of the timberS used, will make
all the difference in the world in the
speed of vessel. Some vessels sail on
one tack better than on the other, The
Maine shipyards are full of such stories.
1t is well known that engines can be
built that are exactly alike, The differ
ence in steamers must therefore be in
the hull If an elaborate series Of cX-
periments was made with two vessels
built on one model the cause of the diff
ference in speed would be found. The
end to be attained is hardly worth the
expense The mystery of the thing is
one of the vanishing legends of the fore
castle. "-NeW York SIN.