CAB37-17 — Page 135

Page 135

CONFIDENTIAL.

Page 135

MEMORANDUM BY THE HYDROGRAPHER OF THE ADMIRALTY ON

THE GENERAL NECESSITY FOR DOCKS ON FOREIGN STATIONS.

do

Page 135

1. THE composition of a modern squadron for the purposes of war must be largely governed by the docking facilities on the station.

2. In the old wars, the wooden coppered ships with bottoms unbroken by any holes could go for long periods without the necessity for docking, and could even by carreening or heaving down improvise means of cleaning the bottom if necessary. But under these circumstances, our naval annals are full of instances where the issue of operations was largely affected by sluggish sailing caused by the foulness of ships bottoms.

3. Of modern men-of-war a very large number are unsheathed, partly on account of the difficulty that has been experienced in finding a satisfactory method of placing wood over the iron bottom, and copper over that, without injury to the bottom from galvanic and other causes, and partly from the extra weight diminishing the initial speed. Owing to the imperfection of all systems of covering the iron with composi- tions, the result is that ships rapidly foul, and their speed is greatly affected, if not frequently docked. In all ships the numerous apertures for valves and the twin screws afford many chances of something going wrong, and in any case they require frequent examination, which can only be carried out in dock. It is not many years since the flagship in the East Indies had to come to Malta to be docked, in conse- quence of her stern tube wearing.

4. Facility for frequent docking is therefore a necessity, even in peace, but the greater difficulty of repairing shot injuries in a skin of steel, as compared to wood, and the greater liability to injuries from ramming or from grounding, add greatly to the necessity in war.

5. On this point it may be mentioned that the risks of war always have, and doubtless always will, largely increase the percentage of ships grounding.

In the old wars, the percentage of ships in commission lost from grounding and foundering, per annum, was over 3 per cent. After the war it stood at first at 2 per cent., coming rapidly down to 1% per cent.-for some years it has now stood at

cent.

per

There are no statistics of groundings as apart from loss, but it may fairly be inferred that they would be in the same proportions.

6. It thus comes about that great risk of disaster is incurred if ships are sent to stations where they cannot be docked, and that the mobility of a large part of a fine navy may be greatly circumscribed, if docking facilities, for the large vessels that would at once form a great superiority over an enemy, do not exist.

7. The rapid increase in the dimensions of ships, so rapid that docks planned a few years ago cannot now fulfil their intentions, makes it necessary to leave a margin for further developments. A wounded vessel may draw several feet in excess of her ordinary draught; so that for the purposes of war, a dock must be considerably in excess of the size ordinarily sufficient. A second class cruiser, for example, may, in such a condition, barely get into docks capable of receiving a first class cruiser.

For the above reasons, any docks specially provided for naval purposes should be of the first class.

8. While ships of the British Navy may be required to be in force in all parts of the world, there are certain parts where, from the paramount necessity of protecting the trade that forms the main source of the wealth of the country, or from the geographical position of other naval powers who may be our enemies, the probability of their being so required is great. These are the Mediterranean; the great routes to the East; and the North American and West India Station.

[206]

B

Page 135

Page 135Page 136