The Sun.
London, England, 1861-07-31 00:00:00

entirely with the weight anti expense of the vertica
and horizontal mass of timber beyond them. Ano.
ther peculiarity was the- eflbrt to, do .way with the
acknowledged source of Weaktiese .evch arises from
holes having to be drilled in. Psf 0 s, s . or the bolts
to fasten them to the ship's aife- 'f.SS arkyAll eases
Ic
where plates have been fracturedfiy hofthe crack
has commenced froth one of .c the r• ~ doles, There
were none of these itylVili. Fairba n -target. The.
v ,li
plates were fastened direellfto ) s .0.:"
outer.-'skin,n
iron fri-
gate would be its oute, ws(i
the target, was repsesenteskby wi Oyin the case of
ts,tght-iron three-
quarters of an inch, tlai, s r rom *tines side of
this were rib -girders e`
~. .e f the sa is,„kincl• as the
iron ribs ,:if a frigat4 iy-es„:, ,e. Tit ' .vsere half an
inch bi:tabont 'll in" ir- :-.e . an itpart, with
stouV`angle irciiid Paste , ii .g. ei,em ti Antes skin.
Frontinsisle this skirl the •rt ets ere 'let into the
plate like topped-screws, ., aengts little more
tlianAultaia)rtli ""s' . E- 13-Sich irito lit plate:
The iron used in this target was of the very best
kind, and the whole of its workmanship was admi-
rable and substantial to the last degree, as the tests
showed. First, a flat-headed steel shot, about Ilb.
in weight, was fired against it to test the quality of
the iron. This made only a dent of from a quarter
to .one-third of an inch in depth. Two of Armstrong's
401 b. shell, filled with sand, were next discharged
point blank at a distance of 100 yards. They also
dented the iron to the depth of some three-quarters
of an inch, but otherwise seemed to have but little
effect, except upon the rivets of the angle iron in-
side the sheathing, which were apparently some-
what started. Two flat-headed 40-pounder steel
shot, fired at the same range, produced more effect.
Their indentation was quite an inch and a half, if
not more, and the rivet heads holding the armour
plates were evidently shaken, though apparently
they held as firmly as ever. The 100-pounder Arm-
strong was next tried at 200 yards, with a shell
filled with sand. This broke one of the angle irons
isonef
gmt
lheyeol iiftnttnlheeerdsasmhmeaaal
glteheriwnr
rivets,
ema
dt
os,ndee a ,
yeta hdedenep
the
practically dent,
wholean
dstsuhtreaprtrtaiersd:
get seemed as strong as ever. A solid 100-pounder
was then tried, and this struck with a tremendous
blow the centre of the
mark, the effect of which
visibly started the plates
a
shots from a solid 68-pound
still more, starting them from the
en
rd
ar at t
th
oe
or curved
shook
they
entire substance and denting them
considerably. A
were bolted,
then fired at 200 yards range. This
theet2khori
ono 1 abuts
g.
emkswho uoht
shot was
ewehi plates
their
s
them been
at 8 0 0
yards, The
nd h
ponderous missile not only made a very deep dent
where it struck, but bulged
the whole target in,
shaking all the plates loose, and breaking some of
the screws which held them,
Still, however, no
lastat shot
e
fired plate gave way under these tremendous visitations,
nor i
a
effect of this was final. By the force of the concus-
sion the upper plate, with one
of the centre small
ones, was completely destroyed, and came crashing
down, leaving those that still remained in a very
wasad a ny
with of
a 100 pounder
shaky and precarious condition. It was, however,
considered by all on the ground to have withstood
the rude assaults it had received in the most extra-
ordinary manner. The screws held on to the very
last, and a great deal longer than any one expected,
while the plates, though, of course, much battered
and defaced, were not only not broken, but showed
no symptoms of becoming so. On the whole, there-
fore, it was considered that the resistance offered by
a target built on this • plan had been most satisfac-
torily proved, and the value of some of its; improve-
ments
established.
The next experiments were made upon a target
invented by Mr. Roberts. This was the very re-
verse in principle from Mr. Fairbairn's, inasmuch
as the thickness of the iron plates was dimi-
nished while the timber backing Was increased.
Mr. Fairbairn's showed how shot-proof frigates
might, with advantage, be made of iron only,
while Mr. Roberts's was designed to prove that
wooden ships could be as easily rendered shot-
proof as if specially built for the purpose. The
back of this target was formed of wrought iron
three-eighths of an inch thick. To this were
fastened iron T plates, which en a frigate
would run along the vessel's side fore and aft. Be-
tween these were fitted oak beams 9 inches square,
which being all tight caulked hold the plates firmly
in their position, so as to prevent lateral bend, and
enable them to resist the maximum pressure due to
their strength. Over this again comes another
layer of beams and T plates, placed vertically, fitted
in the same way and bolted firmly in to the ship's
side. Over all this comes the armour plates. Each
of these latter are 3 inches thick and 2 feet wide,
and made in an angular form, something like a
wide shaped letter V. All the joints are planed so
as to insure accuracy of fit, and thus when a ship's
side was covered with these plates, the alternate
angular projections and recesses would resemble in
shape, on a small scale, the ordinary ridge and fur-
row roofing used in glass buildings, Where the
longitudinal joints occur a recess is cut in the plates,
into which is fitted an iron rib 6 inches wide and
41 deep, the outside face of the rib being also an-