December 7, 1916 
LAND & WATER 
13 
right angles to the grain of the shell body. In shrapnel, 
which carries its fuse in its nose, a solid plate is used. 
In armour-piercing shell, abase plug or adapter, into which 
is threaded the fuse-bush, is itself threaded into the shell 
base. It should be noted that the shtapnel is fitted with 
a loosened head riveted to the shell body by soft wire 
rivets, so that when the time fuse ignites the charge 
within it, the head is blown off and the bullets forced 
forward by the explosion. In the case of H. E. shell, 
with its fuse at the nose, and of armour-piercing shell, 
which also contains high explosive but has its fuse at the 
base, the shell body must be accurately turned inside as 
well as out. Any friction between the container of ex- 
plosive and the shell might easily produce a " premature " 
with wrecking of gun and gun team. In fact, the outer 
configuration of the container conforms accurately to the 
inner curve of the shell body and in addition an air pres- 
sure is introduced into the container which still further 
enhances the accuracy of 
the fitting. You will read- . 
ily see that it is a business 
in which no risks can be run . 
The armour - piercer is 
the aristocrat of the shell 
business. The tempering 
of the head, which is to 
drive through a given num- 
ber of inches of hardened 
steel at a range of several 
miles, is an exquisitely 
exact and difficult business. 
It is impressive to the 
point of magic to see the 
re-heated shell body of a 
giant A. P. set in front of 
the radiometer, which from 
a distance of some fifteen 
yards delicately tests the 
evenness of its temperature 
before it is lowered into 
the rape oil bath which 
gives it an all but diamond 
hardness. 
A Happy Accident 
And there are furthei 
tests with the scleroscope, 
which operates by measur- 
ing the rebound of a 
diamond point on the 
polished surface. But per- 
haps the most interesting of 
all the features of the A. P. is the cap, which is made of 
soft steel covering the head. Its operation seems to 
be the double one of distributing pressure at the point 
of violent impact and of acting as asoUd lubricant for the 
first passage of the shell. The story was told me of its 
hax'ing been discovered by the accident of a compound 
armour plate used in a range test being turned with its 
softer face towards the gun. The armour plate was 
drilled so cleanly and effectively that the deduction which 
led to the fixing of the soft steel cap to the actual head of 
the shell was at once made by some astute observer. 
To get back to the shrapnel. Into the simple shrapnel 
body is placed, first, the canister of black powder 
(which is the active propellant of the shrapnel balls) 
connected by a tube com'mimicating with the time fuse. 
An iron disc is fitted over the canister ; the balls are poured 
in by an automatic machine ; another automatic de- 
vice rattles the shell body up and down to settle the balls ; 
if the weighing machine registers underweight buck 
shot is carefully added ; liquid resin is poured in to embed 
the whole firmly and prevent shifting, with consequent 
dangerous friction and wear of parts ; the head with its 
wooden (or brass) plug is fixed, fuse bush and fuse 
added, and (if fixed ammunition is in question) the cart- 
ridge containing the propellant of the shell is attached. 
This of course in another shop and area. We don't 
gaily court disaster by handling cordite and H.E. in the 
neighbourhood of shell shops. 
The action of shrapnel will be clear from the diagram. 
The time fi'se is set ; the round placed in the gun ; the 
trigger detonates the percussion fuse which fires the chargc 
Inspecting and gauging body of a Fuse. 
which propels the shell from the gun ; the tim" fuse, acting 
at a moment in its flight determined by the skill and 
experience of the gunner, ignites the charge in the canister ; 
which, exploding, forces out the iron plug, driving forward 
the bullets, incidentally shearing oif the head which 
falls clear of the spreading burst. The little clouds 
of white smoke, which appear as shrapnel bursts, are 
made by the black powder and serve as guides to the 
spotters for the batteries. 
With regard to high explosive shells it is to be noted 
that the propellant used is not H.E., but the more con- 
trollable cordite. The activities of H.E. are pleasanter 
to observe at a distance rather than in the chamber of 
your own gun. And we have seen what precautions 
have to be taken to keep the fierce gases of the propellant 
from getting at the more deadly cargo of the shell itself. 
The diagram of the gun in section shows the bare 
essentials of the firing of ordinary ammunition. Behind 
the .shell (its fuse set in the 
base for A.P.'s., in the head 
for all others), with its 
band just ready to engage 
the rifling, lies the charge 
(which may be one or more 
neat silk covered parcels 
of cordite). 
Some Mysteries of 
Ballistics 
Accuracy, accuracy and 
again accuracy. The most 
rigid system of inspections 
prevails at every stage. 
The work of inspection 
carried out by the manu- 
facturers is covered by 
multitudinous Government 
inspectors against whose 
numbers it is a common 
fashion to sneer. Not 
merely safety in handling 
but calculable accuracy of 
range, of burst, of pene- 
tration, is essential. 
Incidentally, the mathe- 
matics behind the practice 
of ballistics is something 
to appal the layman. A 
celebrated mathematician 
F.R.S., has declared 
that all his previous 
flights of calculation were 
babies' play compared with this. And the chemists, 
experimenting with their lives in their hands, add their 
substantial increment to the sum of all this destructive 
wisdom and efficiency. 
Tests and experiments at the ranges form a part of 
the general process of supervision ; but the general run 
of tests is founded on calculations which depend on the 
mathematicians and the formulae of the designers. The 
fact that a range test of a single 15 in. A. P. shell, allow- 
ing for depreciation of the gun and the cost of the shell, 
will work out at something near a thousand pounds, 
may help the grumbler to realise that skilled inspection 
is cheaper, and the financial pessimist to deepen his 
impressions as to the appalling cost of the war. 
Women Serving the Guns 
There is a curious air of calm and, with the exception 
of one or two processes, such as the riveting of the base 
plates and the settling of the shrapnel ball, of quiet in 
the shell shop. As I recall it now with its armies of 
overalled women bending industriously over their lathes 
it might well have been a cocoa factory ; and certainly 
the production of cocoa tins would be an immeasurably 
noisier process. There seemed to me something pecuhar- 
ly sinister in this astonishing quiet, in the apparently 
supreme detachment of workers and management amid 
all these instruments of death and torture. For the 
lathes were grinding out death and worse ; and the pre- 
occupied girls were no other than gunners in deadly silent 
batteries a little behind the lines. Yet stores of 
