The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1879-02-16

Norman WARDS Composite Theory Of Steam
ship Construction Condemned
IRON DESTRUCTIVE TO WOOD
Advantages To Be Gained BY a New A.
rangement ofeBulkheadsl o. als-

The statement of the views of Mr.. Norman Wizard
In of the building composite ships and in con-
domination Of those constructed entirely of iron has
evoked considerable discussion among marine en-
gneers. The opposition to the theory is strong
and outspoken and seems in many respects to be
based upon common sense. A reporter or the
HKnALD yesterday called upon Mr.. Sinclair Stewart
chief engineer Of the American Shipmasters Assoc
citation, and asked HIM
what do you think of this new system?"
Il do not agree with Mr.. Wizard. Iron ships with
iron decks built they ought to be- should be good
enough to weather every ordinary danger Of the
deep. When speak of iron mean American iron,
not pot metal. such many Of the hulls which are
adoat composed Of"
"What are your objections to the composite plany'
Il do not think that wood, in the first place, is
we'll adapted to the carrying of freight at low rates.
On account Of the difference Of their construction
iron vessels carry ten per cent more freight than
wooden vessels of the displacement Their
buoyancy is proportionately greater
Have you pondered upon the proposal made by
the HERALD to corrugate the plates which to form
the fiat sides Of ship, to allow Of their expan-
sion and contraction without the fastenngs being
subjected to a strain p
"Where the decks Of iron the whole ship ex-
pands and contracts at the time. The effect is
with bridge. 1t is not suspended by both ends. but
generally rests equally upon the water"
'But would there not be difference Of temperature
In the parts that in the water and those which
were above it?
II do not think that the difference would amount
to anything in an ordinary vessel The ends. you
know. are sharpening and the curve compensates in
great degree for the lengthening of the plates"
Suppose ship, as is suggested by Mr.. Wizard. is
sailing in the Gulf Stream. where the temperature
impaired to her hull is about 80 degrees. and then
leaving 1t enters the neighborhood OF On iceberg.
Would not the sudden change Of density taking place
in the bottom first be likely to cause wrenching
apart Of the pates?"
''In answer to that would simply call the attsn-
ton Of Mr. Wizard TO the White Star steamers which
cross tho Gulf Stream and the track of icebergs on
almost every trip. have frequently examined them
and have failed to any evidences Of the effects Of
unequal expansion contraction. If any such
thing had ever taken place it would be seen in the
wooden panking of the decks. Wood never shrinks
on end II the upper plates had expanded at all the
Smculty would be very Rerceptinle, there would .
butts We're the change ever SO little this could not
escape observation"
VI DIFFERENCE OF TEMPERATURE.
You admit that there is likely to be some differ
ence in temperature in the upper and lower parts Of
the vessel. DO you notT'
'.what method of obviating its consequences
would you suggest?
''The suggestion contained in the HERALD s
editorial article the other day is very good
The plates intended for tho lower part of the ship
should be placed in position in the process Of
structon ut high temperature. while those for the
upper part should be placed in position at low
temperature
"As to longitudinal bulkheads. have you anything
to recommend further than your statements already
printed in the HERALD?"
In respect to that matter agree with Mr.. Wizard"
"How should the longitudinal bulkhead or bulk
heads be arrangedY
Let there be one bulkhead from the stern to the
athwartshp bulkhead fore of the boilers. and an
other to that abaft of the engines extending to the
sternpost. / would have also two athwartship
bplkheads between the boilers and the engines and
these would enclose the coal bunkers, which it il
necessary to have open good part of the voyage.
BY this plan they would have no connection with
the engine room and thus if the vessel was struck
In the boiler compartment her engines would not DO
disabled. On each side of the engines and boilers
there could be fore and att bulkheads, perfectly
water tight, that on the other hand large hole
In the side could be isolated by closing the bilge
valves and the fires would be protected from the
water"
LONGITUDINAL BULKHEADS
Mr.. Stewards plan is represented in the following