The Sun.
London, England, 1861-09-09 00:00:00

THE BRITISH ASSOCIATION.

AIANCHESTER, SATURDAY.
The various sections resumed their sittings this
morning. There was a large attendance of ladies
and gentlemen in all the rooms.
MECHANICAL SCIENCE.
This section was occupied during the whole of
its sitting with a series of papers, or statements,
and discussion, relative to the best mode of con-
structing armour that should be as nearly impene-
trable as it could be made ; and, on the other hand,
of making projectiles that no armour would be
strong enough altogether to resist. Mr. Bateman,
the president of the section, was in the chair.
The first paper read was by Dr. EDDY, on " A
proposal for a class of gunboats capable of engag-
ing armour-plated ships at sea." He considered
that there was some ground for apprehending that
the heavy armour-clad ships we were engaged in
constructing at such a great expense might be as-
sailed with some chance of success by vessels much
inferior in size and cost, but specially designed for
this service. He wished to elicit the opinions of
those who were most competent to form a judgment
on the subject. Before engaging in an expensive
rivalry by building ship for ship, just such huge
vessels as our neighbours were building, we ought
to satisfy ourselves whether, at much less cost, and
in much shorter time, we could not construct a fleet
of such ships as would paralyse those monsters, if
not destroy them, and which, if numerically supe-

rior, would be a more reliable guard for our shores
than a few large ships, however formidable those
were in themselves. The first condition for such
vessels as he contemplated was a clear superiority
in speed over the enemy. Any invention for offence
or defence that seriously reduced the speed must be
fatal to its success. A second indispensable condi-
tion was such an amount of protection as would
enable a small vessel to some to close quarters with
a large ship and strike home without getting the
worst of it. Granted superior speed, and he main-
tained that small vessels could do anything with
an opponent of vastly superior weight, if able to
approach her without being crippled or destroyed.
If it were impossible for a single vessel ever to
get this opportunity, still it might not be impossible
for one out of two or three to engage the monster.
Might not a flotilla of comparatively small but
active vessels have an advantage over a squadron
of line-of-battle ships ? Whatever steam power
and consequent speed were given to a heavily
armed vessel, a superior rate might be given to
another vessel the armament of which bore a smaller
proportion to her size ; therefore the weight of
metal and speed were, cceteris paribus, in inverse
proportion to each other. By reducing the arma-
ment to a very few guns—two or four only—of the
powerful kind now manufactured, he thought the
required speed, say 16 knots an hour, might readily
be obtained. He would plant the guns so as to fire
rapidly and simultaneously, with a concentrated
force, on any point all round. (Dr. Eddy's paper
detailed the appliances by which he proposed to
carry out this object.)
Captain BLAKELY, R.A., read a paper entitled
"Artillery versus Armour." After thanking the
section for the attention which they had ever paid
him he recounted some of the advances made in the
conslauction of artillery during the past year.
Those views on the strength of cannons which he
had so long advocated had lately been acknow-
ledged to be correct by both the Spanish and
English Governments, and that, too, after a very
long series of experiments, He exhibited a draw-
ing of the new Spanish rifle gun, and explained its
construction. The diameter of the bore is between
six and seven inches. More than half the gun is
of cast iron, the outer portion of the breech only
being formed of rings of steel. The extensive ex-
periments to which he (Captain Blakely) had re-
ferred were made to determine the proper degree
of tension for those rings, because on that point
depended the efficiency of the gun. If the rings
were too tight they burst before the central
part ; and if they were too loose the central
part burst first, and perhaps left the rings whole.
Captain Blakely added that, in his opinion, a great
number of costly experiments might have been
spared had Government placed a little more faith
in his calculations, which were not only made by
himself, but by Dr. Robinson, Dr. Hart, and Mr. J.
Longridge. As to the material of which the gun
ahould be made he spoke with diffidence, disagree-
ing entirely from Sir W. Armstrong. Sir 'William
bad said he could get no steel to answer, and there-
fore preferred wrought iron. He (Capt. Blakely)
had made many dozens of guns, both of steel and
wrought iron. He had used the latter, of various
makers, and steel from very nearly all the steel-
makers in Sheffield, Leeds, and Liverpool ; and,
without exception, he had found all the steels bet-
ter adapted for the manufacture of guns than the
wrought iron. Sir W. Armstrong had alluded to
the construction of guns with wire in a way which
left the impression that Sir William had hopes an

efficient gun could be produced of that materia

lie (Capt. Blakely) had not the slightest doubt of
it', Mr. Longridge had made several very good guns
of it. If it were so easy to build a 600 lb. gun of
solid hoops, it would be equally easy, by using wire,
to make one that would throw a 6,0001 b. shot, or
even a 60,0001 b.
Mr. FATRBAIRN, the President of the Association,
made some observations on the results of experi-
ments on targets at Shoeburyness. He said the Go-
vernment of this country had appointed a commit-

tee, of which he had the honour to be a member, to
investigate not only the sort of plates that ought to
be used in covering the sides of ships of war, but
also the quality of the material which ought to be
e alployed for that purpose, that the best iron or
si ;eel might be selected, and that the greatest pos-
sible resistance might be obtained to penetration
from shot or projectiles of any kind at high veloci-
ties. The committee had been sitting for many
inonths, and a greatmany experiments had taken
'place at Shoeburyness at which he was present.
Thoso experiments generally indicated that although
we had very good iron in this country ; yet, from
what he could learn of the quality of the iron used
in other countries, ours was not quite so good. We
had: iron as good as any other country in the world,
but we had not yet arrived at that point of manu-
facture which should insure uniformity in the tex-
tui:e of the iron, and in the strength of the parts.
H a- believed we should soon arrive at that point,
al ad that the ironmasters of this country would be
able to manufacture plates of good quality, and also
c aloulated in every respect to fulfil the purposes
they were intended for—powerful resistance to shot
-of any description whatever. It would be the duty
of the committee to do everything they possibly
could to defeat Sir W. Armstrong—(hear, hear, and
daughter)—and prevent him penetrating their
plates ; and no doubt Sir W. Armstrong would take
all possible pains to smash them up as fast as ever
he could. From the experiments that had been
made, it was found to be necessary, in order to give
the greatest possible resistance to shot, not only to
Put on plates, but to have sufficient resisting power
behind to withstand the deflecting of the plates
from the velocity of the shot. Where there was a
backing of teak or oak, whenever the shot did not
go right through, the plate was indented into the
wood, so as to prove very injurious, by breaking the
bolts and attachments. His opinion was that the
wood was totally unnecessary ; that it was better to
have iron entirely. He hoped the Government
-would consent to have another target made on the
prieciple that the attachment should be much
sf ronger and better than it bad ever been before ;
and at the same time, that there should be bolts
whi,,h would not penetrate through the plates, to
be screwed in about 12 inches apart, that the attach-
ment might be secure, and the resistance as perfect as
it possibly could be. With regard to penetration of
heavy shot at high velocity, an experiment had been
made to ascertain the exact velocity of the shot, and
be believed that tha velocity of most of them was about
1,100 feet per second. With the target that had been
used, and the strongest gun, an 120 pounder, at 800
yards,
the shot had never penetrated the plates, but
made indentations, and the shot usually slid off at
a certain angle, which was nearly always the same.
All the plates Were laminated. What was required,
in order to
give the greatest resistance to pro-
jectiles of great /763eitY, would be to have the
an possible h
plates as nearly
omogeneons, provided

we could obain toughness, and at the same time
strength. If that could be accomplished, so as to
render our manufacture complete, and our vessels

covered with plates of probably five or six inches,
according to the weight and power of the gun, he
thought that ultimately they might offer powers of
resistance to Sir W. Armstrong, or any other per-
son who manufactured guns, to the power or force
of a 3001 b. or 4001 b. gun. He was strongly of that

opinion • from the experiments at Shoeburyness, and
he believed they would be continued for some time
longer, till we arrived at the maximum strength of
the plates to give the greatest possible resistance to
shot of great weight and at high velocity. He
thought it was also very likely that in the course of
a few months more we might be able to ascertain
what was the best and most accurate system of
attaching these plates, and at the same time what
were the proper thickness and quality of iron to be
employed. (Applause.)

THE ADMIRALTY IRON-CASED SHIPS.

Mr. E. J. Reed read a very interesting paper

" On the iron-cased Ships of the British Admiralty."
After glancing at the circumstances under which
the Admiralty resorted to the construction of iron-
cased seagoing ships of war, he proceeded to point
out the principal features of the ships which the
Admiralty have thus far built, have begun to
build, or purpose to build. Having noticed the
Warrior and the Black Prince, Mr. Reed said the
first of the new ships, the Achilles, which has re-
cently been begun at Chatham dockyard, very
nearly resembles the Warrior and the Black Prince.
The only difference between her and those vessels
is that her beam is slightly broader, and her
floor somewhat flatter than her predecessors',
whereby her tonnage is increased from 6,039 to
6,089 tons, and her displacement from 8,625 to
9,030 tons. All her other dimensions and all
her essential features of construction are exactly like
those of the Warrior, from which it may be inferred
that the method of plating the central part only of
the ship, which was introduced by 'AI r. Scott Rus-
sell, is still viewed with favour by the Admiralty
designers. In the class of ships which come next,
however, the Admiralty have consented to forego
the plan of plating amidships only, and purpose
plating the ship from end to end with thick iron.
But in order to do this it has been necessary to re-
sort to larger dimensions than the Warrior's, and
hence these six new ships, three of which have just
been contracted for, are to be 20 feet longer than
her, 15 inches broader, of 582 tons additional bur-
den, and 1,245 tons additional displacement. As
the displacement is the true measure of the ship's
actual size below the water, or of her weight, it is
evident that the new ships are to be considerably
more than 1,000 tons larger than the Warrior class.
As their engines are to be only of the same power,
their speed will probably be much less. This di-
minished speed is one of the penalties which have to
be paid for protecting the extremities of the ship
with thick plates. Another will probably be a great
tendency to plunge and chop in a sea-way. The con-
struction of such vessels is a series of compromises,
and no one can fairly blame the A dmiralty for build-
ing vessels on various plans, so that their relative
merits may be practically tested. The cost of this
new class of ships will exceed that of the Warrior
class by some £20,000 or £30,000, owing to the in-
creased size. But it will certainly be a noble speci-
men of a warship. A vessel built throughout of iron,
400 feet long and nearly 60 broad, invulnerable from
end to end to all shell and to nearly all shot, armed
with an abundance of the most powerful ordnance,
with ports 9 ft. 6 in. above the water, and steaming
at a speed of from 12 to 13 knots an hour, will indeed
be a formidable engine of war ; and if the present
intentions of the Admiralty are carried out we shall
add six such vessels to our navy during the next
year or two. It has not yet been decided whether
these new iron ships are to have their plating
backed up with teak timber, as in the previous
ships, or whether plating 61 inches in thickness
without a wood backing is to be applied to them.
All that has been decided is that whether the armour
be of iron alone, or of iron and wood combined, its
weight is to be equivalent to that of iron 61 inches
thick. The designs of the ship have been prepared
subject to this arrangement, and provision has been
• made in the contracts for the adoption of which-
• ever form of armour may be deemed best when the
time comes for applying it. I now come to notice
a very different class of vessel, in which the hull is
to be formed mainly of timber, the armour plating
brought upon the ordinary outside planking. The

Royal Alfred, Royal Oak, Caledonia, Ocean, and
Triumph are to be of this class. Their dimensions
are to be—length, 273 ft. ; breadth, 58ft. 6in. ;
depth in hold, 19ft. 10in. ; mean draught of water,
25ft. 9in. ; and height of port, 7ft. They are to be
of 4,045 tons burden, and to have a displacement of
6,839 tons. They are to be fitted with engines of
1,000-horse power. They are being framed with
timber originally designed for wooden line-of-
battle shins, but are to be 18 feet longer than those
ships were to be. They will form a class of vessels
intermediate between the Hector and the Warrior
classes, but unlike both of them will be plated with
armour from end to end. They will be without
knees of the head, and with upright round sterns,
and will, therefore, look very nearly as ugly as La
Gloire, although, in other respects, much superior
vessels, being 21 feet 5 inches longer, 3 feet 5
inches broader, and of less draught of water.
They will also be quite equal to her in
speed. With respect to the armaments of the new
classes nothing has yet been finally decided. I
am able, however, to afford definite information
respecting the number of guns which the various
classes of our new ships will be able to carry.
Of the Defence, Resistance, Hector, and Valiant
I shall say nothing, because they cannot be consi-
dered fit for the line-of-battle, or suitable for any
other service than coast defence. Nor need I say
more of the Achilles than that she will in all pro-
bability be armed with such ordnance as may be
found to answer best in the Warrior and Black
Prince. I now come to the plated timber ships, and
these may usefully be compared with the model
French vessel La Gloire, which is 252 ft. 6 in. long,
has an armament of 34 guns upon her main deck,
and two heavy shell guns forward-36 guns in all.
Now, our ships are to be more than 20 feet longer
than her, and will therefore take two additional
guns on either side, so that they will carry not less
than 40 guns, if the 'ports are placed as close as
in La Gloire. In addition to this, they will doubt-
less have powerful ordnance on their upper decks
for use under favourable circumstances. Let me
now consider the pecuniary phase of this iron-cased
ship question. We may fairly assume that the
average cost of such vessels will not be less than
£5O per ton, and that their engines will cost at
least £6O per horse-power. Supposing these figures
to be correct, then the hulls of the 18 ships will
cost us £4,681,600, and their engines £1,143,000,
together nearly £6,000,000. When masted, rigged,
armed, and fully equipped for sea, they will of course
represent a much larger sum, probably nearly
18,000,000. These estimates will afford some faint
conception of the nature of that reconstruction of
the navy upon which we may now be said to have
fairly entered, in so far as the ships themselves are
concerned. Bat WE. must not conceal the fact that
the introduction of these enormous iron-cased ships
has entailed upon as the construction of other colos-
sal and most costly works. We have now to provide
immense docks for their reception, for at present we
possess none suitable to receive them. Many cm-
siderations combine to exalt the importance of
this part of the subject ; but there is one
which is paramount—namely, that we dare not
send these ships against a French fleet unless
we have docks for them to run to in the event of a
disaster. We know not what may happen to these
altogether novel structures until they have been
exposed to successive broadsides or a heavy naval
battery, and it would be madness to send them out
to encounter a powerful fleet of vessels as strong as
themselves, unless we are prepared to open docks
to receive thorn in case of necessity. 'What is re-
quired in each case is deep water up to the entrance
of the dock, a depth of not less than 27 or 28 feet
at the sill, and a length on the floor of the dock of
400 feet. These things ar• e not combined in any dock
in great Britain, and certainly not in any of ber
In this respect we are far
Majesty's dockyards.
behind our neighbours, who have docks at Cher-
bourg, Lorient, Brest, and Toulon varying from