December 21, 1916 
rLAND & WATER 
9 
requirements of self-defence should have the most expert 
technical consideration in settling the Ihial design of all 
ships to be built. 
Can Submarines be Defeated ? 
But however thoroughly this work is done, however 
e?:tensi\-e and efficient the arming of merchantmen may 
be, no matter in what measure the principle of convoy or- 
protection can be applied, the fact still remains that the 
major problem is to defeat the whole purpose of sub- 
marine attack on trade by stopping it at its source. 
And this really remains a matter of paramount importance, 
quite apart from the degree to which self-defence and 
replacement serve to get us out of our difficulties. By 
this I mean that, supposing all merchantmen, neutral as 
well as belligerent, were ultimately armed, so that the 
rate of destruction was brought down to one-iifth or two- 
lifths of the present rate, and supposing that shipbuilding 
production were brought up to replacing what ^■anished 
when this low scale of destruction had become normal ; 
suppose, that is to say, that only two ships a day were 
going, and nearly two were being daily launched, We could, 
of course, go forward and finish the war without economic 
distress or any slacking of our military etlorts. But 
the world would be face to face with an extraordinarily 
unsatisfactory situation. Tt would mean that the sub- 
marine had made the policing of the seas — which for 
100 years was the sole function of the British navy — 
•flatly and entirely impossible. The world, so far as it 
relied upon seaborne supplies, would be at the mercy of 
the first anarchical Power that chose to proclaim a sub- 
marine attack on trade. Germany, or any other un- 
scrupulous State, might use this threat, just as the 
syndicalists have before now threatened to paralyse 
Italy and France by a general strike of the railways. 
It is a threat so appalling in its implication that we should 
be reverting to the sea conditions of the dark ages, when 
no merchantman could put to sea unless he \\ as prepared 
to fight for his life. It is almost an unthinkable state of 
things, certainly a condition to which Great Britain, the 
premier sea-using community of the world, could never 
resign itself. 
And, for that matter, wc must recognise it to be ex- 
ceedingly improbable that, if the war continues for another 
t,wo years, wc shall be able to rely upon the self-defence of 
. ships, satisfactorily to mitigate, or upon replacement to 
compensate for, the losses if they continue at their 
present rate. And, if the enemy really has the capacitv 
to increase the rate of destruction, then the urgency of 
the wider and more drastic solution is simplj' over- 
whelming.. 
The Only Solution 
The only solution which will make the present situation 
safe, and the ultimate state of things tolerable, is that 
which will result in the majority of the submarines being 
destroyed either before they can win the open sea, or on 
their return to port from it. In the earlier stages of the 
war, it was our success in doing this that brought successive 
submarine, campaigns to a close. The present scale of 
submarine destruction is due to two causes. First, the 
submarines have found means of evading our traps and 
passing our patrols, both coming and going home ; their 
numbers, therefore, are not impaired! Next, the sub- 
marines themselves are designed, armed, equipped, pro- 
visioned and supplied for cruises longer in duration and 
more extended in radius than were their predecessors. 
The consequences, therefore, of a single such submarine 
getting to the open sea is almost indefinitely more costly 
to us than that of one of the more restricted field of action. 
Submarines of the type of the U 53, for instance, have 
a radius of action of over 10,000 miles, have a surface 
speed of over 18 knots, and can do between ten and eleven' 
when submerged. They carry a battery power that will 
take them seventy miles under water. Their guns are 
not the short range weapons that can be folded down into 
the deck, but 4.2's or 5.5.'s, permanently mounted with 
only their interiors and breeches protected from the sea 
water when the boat submerges. Such boats, being 
nearly two hundred feet long, can carry as many as ten 
or a dozen torpedoes, and can rise clear of the water from 
complete submergence, or submerge from beine com- 
'pletely clear, in less than a minute. In size, power of 
armament, radius and speed, they excel the U boats of 
the first campaign by so much as to constitute a menace 
to traihc of an entirely new kind. In the earlier days, a 
■submarine that had passed North 6f "the Shetlands and 
come to the approaches of the Channel, could not operate 
there for a week or ten days before having to begin her 
hon^eward journey. To ten days' piracy then, there 
; w^"e perhaps fifteen spent in coming and going, and a 
great part of these fifteen in the presence of dangers that, 
in the majority of cases, were fatal. The boat of to-day 
spends twelve days coming and going, and is sixty days or 
more cruising on trade routes of her own choice. If one 
is made dangerous, she can shift a thousand miles to 
another. And, as we have seen, the perils of egress and 
return have been reduced to almost nothing. But just as 
originally every stibmarine must emerge from an enemy 
harbour and has, ultimately, to return to it, if once we 
can re-establish danger zones through which it is the 
exception and not the rule to escape, the major problem 
will be solved. But not till then. 
'I have purposely abstained from discussing how it is 
that submarines have found means of escape and how 
the ascendancy of our attack can be restored. They are 
both things that have excited the curiosity and, if I may 
say so, the suggestive facilities of readers to a high point. 
One propounds a theory that the principles involved in 
wireless telegraphy are capable of application to this 
matter. Another asks how far developed is the principle 
of under-water communication with which we were all 
made so familiar ten years ago, when proposals were put 
forward for keeping ships in communication both with 
shore stations and with each other, by means of bells 
or gongs kept in flooded tanks. Strokes on these gongs 
were, it will be remembered, found to be distinctly aud- 
ible by special telephones at very great distances indeed. 
Other correspondents have suggested that science has 
advanced along the lines of measuring and detecting ex- 
traordinarily minute movements of the earth by the 
seismograph. Why should its principles not be applic- 
able to supply a warning of the approach of propeller- 
driven craft at sea ? It would really be better if those 
who have suggestions of this kind to make would forward 
them direct to the official authorities who, we may be 
sure, are keenly alive to the requirements, and if they 
know their business, are far from blind to the possibilities 
which modern knowledge has opened up, 
Hearing a Substitute for Sight 
That there are manifest ways of getting some in- 
formation in certain conditions by substituting hearing 
for sight under water, is clear enough. And what is 
very much to the purpose is this. In proportion as these 
possibilities are developed, so must the importance of the 
submarine diminish. I remember about ten years ago — 
it was at the time of oneof theeariiest, if not of the first 
submarine disaster— taking part in a discussion, with a 
party of na\al officers about the application of the under- 
water bell principle to maintaining communication be- 
tween ships and submarines. And the opinion was put 
forward that, if ever this principle w'as brought to scien- 
tific completeness, it must give the submarine such 
accurate po\\-ers of gauging the approach, either of a 
single ship and still more of a fleet, as to make the con- 
tinuance of surface fleets impossible. This naturally 
led to a canvassing of the general pro and anti submarine 
case and we separated without agreement as to the trend 
of future developments. A day or two later. Lord Kelvin 
.came on board the JiipHcr, where certain fire control ex- 
periments of mine were being carried on, and I repeated 
to him the upshot of the conversation. The case for the 
submarine was that, being unseen, it could approach 
in absolute secrecy and, carrying a weapon at that time 
thought necessarily fatal, it seemed manifestly marked 
for decisive employment when the opportunity for em- 
ployment came. Tlie disadvantages of the submarine 
were its blindness, its low speed, and its vulnerability 
on the surface. A surface ship at sea and at high speed 
could ne\er be caught, and, rarely only, waylaid by the 
submarine. So that it seemed as if protection was chiefly 
:a matter of care, vigilance and the prompt and effective 
, use of guns. And I asked him if any conceivable develop- 
ment of under-water hearing, could coinpensate for the 
