The sun., 1891-02-10
THE ARMoR TRIAL At poRrsxopru
A Performances which does Not Ovsrthro-
tho ResNlte Obtained ~ AnnspolssL

THE ARMOR TRIAL AT P0RTsMoUrH
A Performances which Does Not Overthrow
tho Resnlte Obtained ~ AnnapolSs.
II the test Of shefleld compound pl.,s
which has Just been conducted by British Ad.
miralty officers at Portsmouth. IL intended az
an Offset to tho three successive defsets ana.
tained BY this kind Of armor at Annapolis
Amaeer. and Ochta, It must evidently isil oi
its purpose.
Fridays trial was held on board the Nettls
where the armor Of the Royal SOVEREIGN was
tested last spring. The plate. as In the Anna
polls contest, was feet long by feet wide.
but only inches thick. instead OF about fox
as In the Royal Sovereign and Ann apolis triols
It represented section Of the armor made bv
Charles Cammell 4 Co. for cruiser now under
construction by the Lairds at Birkenhead for
the Argentine Republic. The system Of manu-.
facture was the Same as that Of tho Cammell
plates tosted at the American and the Danish
proving grounds last fall
According to the cable accounts Of the Rerah
the plate, at distance OF 80 feet, was attacked
by three rounds from a 6-inch brooch .loadinp
rife. loaded with 10O.pound Palliser chilled
projectiles, propelled by charges of 50 pounds
Of powder. The striking velocity was ,bos
feet or second and the striking energy 100
foot-tons. The account proceeds to say that
oil three projectiles were completely broken
m; that mono Of them penetrated tho plato
moro than two inches. and one only IN inches:
that whilo few hair.like cracks were de
velopod In tho steel face. mono extended
through to the softer metal In the rear, 20 that
It may be assumed that there was no bulginr
OF the plate into the backing.
That this test, as far as Il went, was a
triumph is obvious: and It further appears to
have been specially intended to contrast with
the test Of Schneider steel plate last May at
Gavres. whore. however tho conditions wers
vastly different. since tho French armor. made
for Chtlian cruiser, tapered from about 8
inches at the maximum to about 5k at the
minimum. But. leaving that comparison for
what 1t Is worth. o little examination will show
that Fridays test at Portsmouth doca not ot
NIL counterbalance the defeat which tho com.
pound armor received in tho September com.
peti,ive trial ut Annapolis from q gun Of the
same calibre.
The powder charge at Portsmouth was only
80 pounds, while tho charge at Annapolis was
Az. The striking velocity at Portsmouth was
but 1,5G6 feet per second. whtlo at Annapolis Il
WAS 2.075 feet The striking energy at Ports
mouth was about 100 foot-tors whilo at An.
papolis It was 2.9ss. These comparisons will
show at once why at Portsmouth the Calnmell
plate completely resisted tho 6-nch proleotilos
Tired against 1t. whereas at Annapolis prolec.
tiles OF the same cnlibra ruined u plate Of tho
same makers ~ inches thicker. in the Por a.
IN no case fully perforated even by the point OF
the prrIectie: but at annapolis. whore four q.
S oca q da1S ARA e
Admiral Kimberly was President declared that
the c9mpound plate was perforated by all the
both plats ana bseklnE.
test Fday WAS
arranged 80 that the armor plate should not DO
dortroyed., In last springs trial Of Cammell
velocity Of .976 feet per second was impartedto
Q shell OF the same weight in a gun Of the same
the Velocity to. only 1850 ieet per second was
q psFEiETatinG hs target In the former ,rls
backine II was safe to assume that the same
az inches less thick. The great reduction
ag Psp Rsss II S sp pss sss Ss ss
s@ys vessel Viii sarry he same ser9lSs % eSarss 81 re
e'6sr Ss'n the
SnS ssns %n s % y fs se H
faa so Ct
gun and SS75 IN the Aneriesn. At Tie I prev oSs
ssas oi 1edacS saSna his 1ss;s sss o
Of consideration for the armor It might have
been as instructive ms 70 substitute q 6-inch gun.
1nether fact 70 b noted in this trial at Porss.
mouth is tnt Pallisrr projectiles were used,
the Firminy against steel arnor. The Pallisor
osed Tse oamer as p a.mo one
serated hy the very fact that all tn iee wero
comnletely broken Up into dust" as tho so:
low !sos of ee Ssr sssona and hs
other hand y 4. Anpap1lls: .n With 2.015 feet per
sssei osva.heoded M % proieetles Went Snfe"s eo
pletely throncI tie. lO.-inch Cammal' plate
ef TIE last one: which went through The
largest niece, lodging 30 feet nwat. Had
such shells been used in.. Fridays trial.
even with the low velocity emplo"e a
Cammeli plate to armor-pisrcinR proiectiles
might hnva been obtained. It must also bo
observed that when tho hard steel face of tho
the Wrought iron behni it It much G more riSi; easily
yields. so that the fractional extent OF the
penetration in Fridays test was not an evact
Indication ,, o. The strength Of tho compound
The conclusion mnst be that the demonstra.
ton made list September at Annapolis Of tile
inferiori,y Of tho com .onnd to the nickel steel
degree Iy the trial mt Portsmouth. Indeed this
latter. vi th its three rounds at low veloctt os.
compat cd with tho I've at Annapolis, the last
Of which was from an eiTht-inch gun. becomes
too eminent conrtssv and consideration on the
part OF tho gun Tor tho tDrEet.
IS TIMES THE pKIyLEY TARIFF.