A NEW MODE of CONSTRUCTING VESSELS OF WAR WITH DUE REGARD TO THEIR PROTECTION FROM SHOT AND SHELL
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by Ludwig Eggert and Otto Ernest
Pohl at the Office of the Commissioners of Patents, with their
Petition, on the 16th April 1869.
We, LUDWIG EGGERT, of Konigsberg, in the Kingdom of Prussia,
Shipbuilder, at present temporarily residing at Liverpool, in the County of
Lancaster, and OTTO ERNEST POHL, also of Liverpool, aforesaid, Merchant,
do hereby declare the nature of the said Invention for "A NEW MODE of
CONSTRUCTING VESSELS OF WAR WITH DUE REGARD TO THEIR PROTECTION FROM
SHOT AND SHELL," to be as follows:-
The study of the system of construction of armour-plated vessels as
they are in existence at present and the results of the trials with shot
& shell against targets representing the sides of such armour-plated
vessels have shown that the principle does not answer the purpose for
the following reasons, viz. :-The vessels are becoming more & more
unseaworthy the heavier the plates fixed on their sides, which is
proved by the printed reports of the English Admiralty regarding the
behaviour of the vessel when in a seaway. We notice a gradual
increase of this unseaworthiness in the latest constructed vessels without
obtaining the object of making them shot-proof, & the great improvements
in guns & shot remove this object more out of our reach than ever as
long as we go on with the present system. The armour-plate targets

page_text: show in the trials that vessels built from such patterns would have their
sides so much injured by projectiles discharged against them that they
might easily be sunk, or if they escaped such a misfortune the repairing
of the effects of a few shots would entail heavy expence besides taking
up considerable time. It being an acknowledged fact in land fortress
defence that brick or stone walls are easier destroyed than sand walls,
but the latter combined with the former so as to protect the stone or
brick walls make an impenetrable structure, this led to the idea of
searching for something similar in protecting a vessel of war from
projectiles. Such substance & its employment for the purpose found
it was necessary to alter the construction of vessels of war. Extensive
calculations based upon the reports of the observations of the latest
target trials in England & Prussia, & further private trials with
projectiles (both explosive & massive) at a distance of 70 yards
against a timber target of a certain construction opposing to the shot
the ends of the fibers of the wood, have proved that the timber is not
destroyed by the projectiles, but the projectile enters forcing the
fibres out of its road in circular form, & the friction produced by this action
of the projectile lays the same dead at a comparatively short length of
the timber; further the hole made by the projectile closes up as soon as
the projectile has passed through. The aforesaid was the result of
massive projectiles, & with regard to shells employed against the
same target the following results were obtained :-The first shell left no
explosion results to be noticed at all. The second one entered in
exactly the same place as the first, & when exploding brought forward
a few longitudinal fibres of the diameter of ordinary matches & the
gazes of the explosion escaped through this opening. In taking to
pieces the target it was found that the shells after entering the timber a
few feet had exploded & made a bed for themselves in shoving the
fibres aside & compressing them. Further the immensely important
result was obtained of the certainty of localizing the pernicious effects
of projectiles in a ship's wall constructed on such a principle, viz.-
opposing to the projectiles the ends of the fibres of timber, for any
destruction in the protecting timbers could be easily repaired, which will
more clearly appear when we talk about the construction of the war
vessel, to which we have to pass now, & which constitutes the second
part of the Invention.
Description of Midship Section.-The displacement being calculated
& the area of the greatest midship section determined, we construct

page_text: the same, marking the load water line according to the calculations; we
make another mark below the water line down to that point where
projectiles passing through the water & touching the body of the
vessel will prove ineffective. From this mark downwards the under
body must be constructed according to the size of the vessel of wood
only. On the top of this structure we put our first deck beam of iron.
On this beam rests the one of two other iron bodies which form the
interior of the vessel. On the top of this first iron body rests the second
iron body, in such a manner that the top of the one body forms at the
same time the bottom of the other. The sides of these two iron bodies
consist of circular vaults. The second deck beam is laid on the top
of the lower body, passes then through the circular sides of the top body,
& extends to the construction line of the midship section. On the top of
the upper body is laid the third & last deck beam, in the same manner
extending over the sides of the top body as described in the previous beam.
Description of the Sides.-Between these beams protruding from the
iron bodies at a certain distance we arrange the protecting material in
the following manner:-We take iron plates of the same width as the
beam extends over the iron bodies, fasten them to the first deck
beams, & lead them to the second deck beams in a diagonal
direction. In the same manner we continue between the second &
third deck beams, then we follow up the same process in the
opposite direction, so that a quantity of square boxes is formed
covering the ship's sides. These boxes we fill with timber in such a
manner that the fibre of the timber runs parallel with the plates of
which we constructed the boxes. The gun ports are to be arranged
on the first 'tween decks in such a manner that each one fits into one
box only, & does consequently not disarrange the iron used in con-
structing the boxes. From the top of the gun ports the line of the
middle section moves in a circular way up to the deck. In filling the
boxes with timber we said before the fibres of the timber are to run
parallel with the plates of which we construct the boxes, but as this
does not determine our meaning quite clearly we further say the filling
with timber must at the same time be done in such a manner that the
ends of the fibres form the outside of the vessel.