MINUTES OE PROCEEDINGS OE 
412 
As to 9-inch guns, Mark II., only a few have been made, as the experi¬ 
ments (see p. 409) proved that the longitudinal strength of a forged breech- 
piece was superfluous when a solid-ended steel barrel and long or jointless 
breech coils were employed, and moreover that it was not only a source of 
circumferential weakness, but rendered the gun liable to burst explosively. 
The following table* shews the number of each nature on the various 
constructions issued up to the 17th February, 1870 :— 
Original. 
1 
“ Eraser,” 
with forged 
breech-piece. 
“ Eraser,” 
with triple 
breech coil. 
“ Fraser,” 
with two 
breech coils.f 
Total. 
13-inch, 
23 tonst.. 
2 
_ 
_ 
2 
12 
23 „ .. 
4 
—, 
— 
— 
4 
12 „ 
25 1 . 
— 
— 
11 
H B 
11 
10 „ 
18 „ . 
— 
. —'! 
17 
— 
17 
9 „ 
12 „ ......... 
191 
26 
134 
19 
370 
8 „ 
9 n . 
76 
6 
27 
— - 
109 
7 „ 
7 „ . 
50 
2 
61 
— 
113 
7 « 
6* „ . 
328 
20 
226 
—• 
574 
Details of the Manufacture of a 9-inch Gun , Mar7c III. 
The gun consists of:— 
An inner barrel or tube of steel. 
A B tube. 
A breech coil. 
A cascable. 
The Inner Barrel. 
The inner barrel, which when in the gun weighs only 36 cwt., is made 
from a solid forged cylinder of cast steel weighing 67 cwt., which is supplied 
to the Royal Gun Factories by the contractors, Messrs Firth, of Sheffield. 
Casting is necessary, not only for the purpose of obtaining a sufficiently 
large block of steel, but also for making the block homogeneous and uniform 
* I Lave purposely excluded 64-prs. from tlie table, because tbey can hardly rank now as heavy 
guns, and moreover they differ from all the higher natures in having coiled iron barrels, shunt 
rifling, and a peculiar construction—a different class in fact. There are 432 64-prs. of 64 cwt.; 
of these 161 are on the original construction (or Mark I.), 50 B pattern (or Mark II.), and 231 
D pattern (or Mark III.); see plate 1. There are in addition 212 64-prs of 71 cwt. converted 
(at Elswick) from 8-inch cast-iron S.B. guns of 65 cwt., and more are undergoing conversion in the 
Royal Gun Factories. 
f i.e., two breech coils shrunk one over the other; in the 9-inch gun (Mark IV.) the inner one is 
a single, and the outer, to which the trunnion and C coil are welded, is double. In the 10-inch 
(Mark II.) both breech coils are double. 
J Rifled guns of 7-inch calibre and upwards are officially designated by their calibre and weight, 
but guns below 7-inch calibre are known by the weight of the shot. The weight of the gun is 
always expressed in tons if 6 tons or upwards, otherwise in cwts. To designate fully any gun, it 
should be stated whether it is B.L. or M.L., and the mark should be specified, thus:—'The 7-inch 
rifled M.L. gun of 7 tons, III. 
