The cutting of submarine cables during war, has for its object the interruption of intelligence and is merely one of the operations incident to breaking the enemy's line of communications, the latter, a term of broad scope, although chiefly applied to the means by which an army or a fleet is kept in touch with and supplied from its base. It is evident that whatever interrupts the forwarding of stores and ammunition (the material needs of an active force), or the interchange of information and the delivery of orders (its moral needs), must of necessity deal a serious blow either through stopping the stream of provisions and munitions of war, without which an army becomes innocuous, or by intercepting the messages of information and instructions upon which depends the proper handling of the troops or the ships. According to the circumstances of the case, the latter may indeed be as Pregnant with military results as the former. It was with masterly comprehension that Napoleon remarked "le secret de la guerre est dans le secret des communications," an aphorism illustrated by his own successful campaigns of Marengo, Ulm and Jena, and by his disastrous advance into Russia. In more recent days, it was the control of the lines of communication which enabled Admiral Sampson to work out his scheme of campaign with a completeness now historic.
Modern treatises on the subject, recognizing the importance of that branch of the communications which relate to the transmission of intelligence, discuss at length the duties and responsibilities of a director of telegraphs on the staff of the general commanding and the details of the field postal service. In the war of 1870 there was a director of military telegraphs on the staff of the commander-in-chief, whose responsibilities are briefly described by von Schellendorf in his "Duties of the General Staff" as regulating "the whole telegraph service in the theatre of war." In our war with Spain the telegraph service was undertaken by the army signal corps with but indifferent success. Its attempts to interrupt the enemy's cable communications failed utterly, but that is another story which you may hear later. Says Col. Furse, C. B.: "Notwithstanding these disturbances, no commander in our days would think of taking the field without the aid of the electric telegraph. Who can fail to appreciate the immense advantage it is to him to possess an exact knowledge of all that is passing in the scattered parts of his army? Consider the benefit of his being able to place himself in direct communication and interchange views with his subordinates; with what confidence he can give directions, impart the result of the operations of lateral columns, indicate the assistance to be expected from them, and the time likely to elapse before this aid may reach its destination. Look how the operations of two or more armies, separated by some impassable natural barrier, have ceased to be such a risky thing as they have hitherto been; for, thanks to the electric telegraph, their commanders can now combine their movements and can be in constant intercourse." This picture of the strategic conditions of warfare on shore is a but a tiny miniature when compared with the vast canvas required to depict the operations of fleets and squadrons. The distances in the one case are measured by single miles, in the other by hundreds of leagues. No wonder our late commander-in-chief determined to gather into his own hands the nerve threads which brought into touch his widely-scattered squadrons and to sever those which kept Cervera constantly informed as to his enemy's movements. No less essential it seemed to Sampson to hold the one than to destroy the other. It was not necessary to teach him, in the words of the author already quoted, that "The destruction of telegraphic communication between the enemy's forces and their base, and with the provinces on either flank, is a great object in war." It was the submarine cable which told Cervera of the attack on San Juan, Porto Rico, and thus turned him away from the destination to which he had been ordered and which Sampson had rightly guessed. Had the lines leading to Porto Rico been promptly cut at the outbreak of hostilities, Cervera would have met, off San Juan, the fate which befell him on the 3d of July, and the war would have been over before it had fairly begun.
It follows from these preliminary considerations that accurate information as to the location of all submarine telegraph lines should be at the disposal of our commander-in-chief that he may know where it will be most advisable to send a vessel to cut such lines as lead to the enemy's territory. This is no new suggestion. Although our experience during the war with Spain demonstrated its value, the suggestion itself had been previously made in one of the most important papers ever read before" the Royal United Service Institution of Great Britain. Pointing out in 1881 the pressing necessity of establishing an Intelligence Office at the Admiralty, Sir John Colomb mentioned, among other duties, "It is also of importance that all particulars concerning the exact position, nature of bottom, and depth of water in which submarine cables are laid should be collected and furnished to naval commanders, so that they may know where to cut or tap them, or prevent others from doing so."
I am unable, through ignorance, to state that our own excellent Office of Naval Intelligence is in a position to supply this information with that exactness which Sir John had in contemplation when he wrote the words just quoted, and I am disposed to believe that the difficulty of obtaining this knowledge is so great as to be for us practically insuperable, since substantially all submarine cables, the world over, are owned by foreign corporations and controlled by foreign governments. It is not likely that these corporations would reveal the location of their various lines so frankly and so fully as to facilitate their destruction in time of war. While not pretending to assert that the precise information which would have been so valuable to us in 1898 was not in the possession of our Office of Naval Intelligence, yet I may say that it did not reach either of the parties that undertook to cut the lines leading to Cuba.
The lack of definite knowledge of the locations of cables does not, however, operate as a hopeless bar to their raiding. The terminal points are known to every one who cares to consult the diagrams of cable connections which are freely open to the public, and which are printed by our own Hydrographic Office. If therefore you are directed to isolate any place or territory telegraphically you will easily learn the points where the cables land, and where they originate.
To trace the intermediate route is not very difficult, if you keep in mind one factor of determining importance. Of course you will, in this way, only get an approximate, or probable, location, but you will not be very far from the truth. This factor is cost. Each deep-water cable is worth about one hundred pounds sterling a sea mile, and each knot saved means less capitalization and greater economy in laying and maintaining. You may be pretty sure therefore that the wire you seek has been run in a straight line, or as nearly in a straight line as topography and hydrography permit. Along a convex coast line it is to be sought not far from the beach, and preferably in not less than 30 fathoms. Along a shore-line consisting of capes and bights it shaves the points. In no case is wire unnecessarily paid out, and this hint will give you the clue you require. You may with confidence lay down on your chart the probable course of the cable from start to finish and then take up the next question in order—where is the best place to attempt the grappling? Military considerations may confine your movements to a narrow zone. In this case you have no choice and you must do the best you can under the circumstances. If, on the contrary, you are free to go where you please, you will study the chart with care and select a point where the water is shallow and the bottom free from rocks. In deep water, much time is consumed in making a "drive," as the trip across the line of the cable is called, and the difficulties attending the hooking on and heaving up are greatly increased. On rocky bottom the cable lurks among boulders; a grapnel is apt to pass over it without hooking, or to be caught on a stone and its prongs straightened out like an umbrella turned inside out by a sudden gust of wind. "I may remark that the two cables from Santiago to Cienfuegos come under the head of cables protected by the nature of the bottom. We made in the St. Louis and Suwanee no less than fourteen drives for them at points varying from just outside the harbor mouth at Santiago to ten miles distant, but we never succeeded in getting the wire or in bringing up anything more than the grapnel itself with its prongs straightened out. The Santiago-Cienfuegos cables were our conspicuous failure." Should the bottom be shelving the drive is made up hill, or from deep water into shoaler water. It is hardly necessary to add that the direction is square across the lie of the cable.
You have now determined upon the place where your search is to begin and upon the general line to follow. Let us consider briefly the mechanical means to the end we have in view.
The appliances needed by a ship assigned to the duty of cutting cables are few in number and simple in nature. They consist essentially in a suitable instrument for grappling the cable, a stout and flexible line attached to the foregoing and a steam windlass or capstan for heaving in. It will be apparent on reflection that the first is more likely to be a special tool than the others and one which, in its higher development, is not likely to be found in the naval service. A sounding machine capable of reaching bottom at a thousand fathoms or more may be very helpful but it is by no means indispensable. If you cannot get a cast with the lines you have, you must do as I did off Santiago, use the grappling hawser itself for a lead line. Other things being equal, the best results in all mechanical operations are achieved with apparatus designed solely for the particular task in hand, and containing in its plan and workmanship the highest skill, deepest thought, and Widest experience of the expert. The job can be, and often is, done with inferior facilities, but time, labor and patience must be expended to replace the unerring precision and rapid output of the special machine. A few words devoted to study of the most successful forms of grapnels will not be amiss, for the latter will convey hints as to improvising, which may prove of great value. If we pause to reflect upon the way in which a cable rests upon the bed of the ocean, we shall realize that the conditions may so vary from place to place as to present a wide diversity of problems to solve, the variable being for the same cable, the changing character of the bottom. The cable may hang in a long bight from crest to crest of a valley; it may lie on a generally level floor yet nestling among boulders and rocks so closely as to be almost secure against grappling; it may rest easily on a hard bottom; it may have sunk deep into mud and ooze. Plainly what will pick it up in one case will fail to dig it out in another; what will dig it out here will not get within its stony guard there. And so we find that the nature of the bottom has forced the clever men charged with the maintenance and repair of submarine cables to devise grapnels appropriate to the particular needs in each instance. Fortunately we may, in a rough telegraphic fashion, divide ocean bottoms into three classes, soft, hard and rocky. If we know, in a general way, what tools have been invented for use on these three classes of floor, we shall be helped in our improvising when it falls to our lot to drag for a submarine cable.
The exemplar and forebear of them all is the grapnel known to sailors from the earliest ages. When it was found that the ordinary grapnel was too light, the weight was increased up to 5oo pounds as a maximum; 200 pounds may be accepted as a good working figure. It was soon seen that the short shank and the long prongs made a grapnel jerk and jump on hard bottom, so for this latter use the prong was shortened to a scant hook and the shank lengthened. Neither of these forms being satisfactory among rocks, it occurred to some nameless expert to use a heavy bar of iron or steel about 4 feet long provided with numerous short hooks distributed along its four sides, trusting to its shortness and its weight to search out the interstices between boulders and thus seize the cable in its hidden lair. Such was the origin of the fitly named centipede, the third of the types of grapnels employed by cable ships. I have mentioned them so far in their simplest form, but it is not to be supposed that so highly organized and costly a service should not have evolved modifications to meet certain difficulties which arose from time to time. Thus you may readily imagine a grapnel to have picked up a cable and, before being lifted clear, to have caught its prong in a rock. The simple type would have opened out the prong and have lost the wire. Here ingenuity entered and suggested either a spring which would hold the prong extended except in the event of too great a strain, on a prong held in position by a soft pin. In the first instance, the spring returns the prong to its place when the strain is eased up; in the second, the pin of lead or soft iron is sheered, the prong swings open on its hinge, but in both cases the cable is still held by the shoulders of the lugs between which the prong revolves, or by projection on the shank itself. With the simple grapnel this same end is secured, sometimes, by a spring which holds the cable even if the toe straightens out. Another improvement is sought in a means by which a cable, after being grappled, may be cut, one end dropped and the other firmly held, brought to the surface. Should any of my hearers care to dip deeper into this subject they may consult Prof. Jameson's paper on "Cable Grappling and Lifting" in the Journal of the Society of Telegraph Engineers, Vol. II; the Electrical Review, for January II, 1895; Mr. Frank Lambert's paper read in 1876 before the Society of Telegraph Engineers on "Grapnels for Raising Submarine Cables in Deep water "; Mr. Chas. Bright on Submarine Cable Grapnels, Engineering, November 4, 1897, etc. The illustrations to which I shall now refer may be found in the latter article. Fig. i is the short-toed grapnel for use on hard bottom, such as sand and gravel; Fig. 2, the long-shanked, long-toed grapnel, for use on soft bottom, such as mud and ooze; Fig. 3, the conventional form of centipede.
In a centipede ordered for the St. Louis, but never used on account of the speedy collapse of the Spanish resistance, a five-inch iron pipe was substituted for the bar. Holes were drilled through it from side to side, square bars of 3/4-inch steel about 15 inches long were forced through these holes, the ends bent in the same directions, and the metal upset to hold the claws firmly in place.
I have thought it well to exhibit a grapnel of special make to illustrate one successful manner in which the problem had been solved. Fig. 4 shows two Stallibrass grapnels coupled together for centipede work, and Fig. 5, the details of the grapnel itself. The toes are pivoted about the bolt A, their heels resting against the soft iron pin B. When the strain is too great the latter shears and the toe drops into the dotted position, freeing the grapnel from the rock or other obstruction, but the cable remains caught and firmly held in the round seat shown in the figure. A capsized toe tends to throw the grapnel over and a sound toe down, something which invariably does not happen with the ordinary Frapnel. It is stated on authority, that so long as one toe is in its normal position, the Stallibrass grapnel may be relied upon.
I will not waste your time over the so-called "Cutting and holding Grapnel." If you should need one it will be better to buy the tool, of which, it may be remarked, numerous varieties are in use.
It is always well to place a length, say 15 fathoms, of half-inch chain ahead of the grapnel. The object is two-fold, first, to weight the ring of the grapnel and thus hold it down to its work; second, to avoid chafing the line. It may also be seen that such a chain will fall into the spaces between rocks and so guide the grapnel to its object. As there can never be any disadvantage in using the chain, and as it is frequently of great utility, I suggest its employment as an invariable rule.
The line or hawser may be anything stout enough for its purpose practically you will be doubtless thrown back on what is available. The depth of water will suggest an appropriate size. But a heavy "shore end" may demand in grappling as strong a hawser line as a lighter cable laid in deep water. I have personally used manila hawsers from 5 to 8 inches in circumference, but, for the reason that no others were to be had.
The operation of grappling is directed by one officer who keeps his hand on the hawser and from the vibrations which it transmits from the grapnel hundreds of fathoms below, he forms an idea of what is going on at the bottom, which is correct in direct proportion to his experience. Little shocks, like a succession of tremors, tell him that the grapnel is slipping along a reasonably smooth floor; a heavy strain followed by a sudden release, that it has fallen among rocks; a gradual increase of tension always accompanies, although it is not the invariable proof of, the hooking of the cable. From these facts it will become evident that the lighter and more flexible the grappling line, the more truly and delicately will it transmit the vibrations originating at the bottom, and the more accurately may these vibrations be interpreted. Use therefore the lightest line of sufficient strength. Here again, special wants have brought about special means, and the grappling line is now as much an article of manufacture as the submarine cable itself. Strength is secured by the adoption of steel wire (galvanized to prevent corrosion), and flexibility is gotten by using many fine wires, laid up into seven strands, each strand wrapped in tarred hemp. Get this if you can, but remember that it is a convenience only, not a necessity.
The cable ship inserts a dynamometer before the winding-in machine to obviate heavy surges. The same end may be reached in a cruder and less effective manner by a steam winch with a variable throttle in the hands of a skilful person who acts in obedience to signals from the officer in charge.
A cable may be hove up by a windlass or capstan out of sight of the grappling officer, but the chances of breaking the wires are thereby enormously increased. If your forecastle winch is too small in the heads, for rapid work, it may be necessary to enlarge the latter by wooden chocks or whelps—but avoid the mistake of making them so large that the winch power becomes inadequate.
While the smaller ship is handier, there is no real limit to the size of the vessel which may be used for this purpose. My own experience was had in the Suwanee, in the Wompatuck of 460 tons displacement, and the St. Louis, displacing 17,500 tons, the largest vessel, by the way, which ever flew a pennant.
On arriving at the spot chosen for cutting a cable, the first thing to do is to stop the ship dead in the water and ascertain the depth, unless this is given by the chart. It is possible that you may not have enough sounding wire to reach the bottom. This, I have said, was my case off Santiago. There is then nothing left but to lower the grapnel over the bows and bend on hawser after hawser until the grapnel strikes the bottom. You will have taken such a position as will enable you to drag up hill and you will begin the drive far enough on one side of the known or assumed line to be certain that the wire lies ahead of you. The dragging is always done over the bows, as that is the one end of the ship which may be controlled. The grapnel is on the weather side to keep the line clear of the screw. The more slowly the ship moves the more likely is the grapnel to seize the cable. Her advance should be so gradual as to be hardly perceptible. The best way of measuring her speed is by means of a "Dutchman's log," small billets of wood thrown upon the surface of the water from time to time. "The grapnel creeps over the bottom, its prongs burrowing slightly under the surface of the soil until they catch underneath the cable. The gradually increasing ten- !ion on the grappling rope reveals to the expert, whose hand is always on the outboard part, that the cable is caught * * * * . It is well to keep going ahead for a few minutes after getting an unmistakable bite in order to lift the cable off the bottom, and thus ensure its being hooked. Then the ship is stopped and the line, taken to a steam winch or capstan is hove in. As soon as the bight is well out of water, a hawser is bent to it and the grapnel relieved of its duty. When the cable is inboard, a stout plank to protect the deck, a couple of sharp blows with an axe and the thing is done. Letting go one end and steaming a couple of miles away with the other will make a gap of sufficient magnitude to embarrass the repair steamer, should she come along before peace is declared."
In 1898, cable cutting led to certain very exciting episodes, and to one affair which may be fitly mentioned in the same breath with Cushing's attack on the Albemarle. I allude to Winslow's and Anderson's gallant work at Cienfuegos, described at length in the Century Magazine for March, 1899. If any one should take sufficient interest in my own experience on May 18, 1898, when for eight hours the St. Louis and Wompatuck lay within easy range of the batteries at Santiago with which for threequarters of an hour they were in hot action, he will find the official report in the well-known appendix (Bureau of Navigation's) of 1898, and a brief popular reference in the PROC. NAV. INST. No. 93, p. 163
In conjunction with the St. Louis' usually successful efforts, I cannot refrain from recalling an occurrence which many of you doubtless witnessed early in June off Santiago. "About this time the Army Signal Corps was vainly endeavoring to get the remaining Santiago-Jamaica cable, the one which it seems the St. Louis had left intact on May 18, although I had reason at the time to believe it broken. The Corps had chartered the cable steamer Adria, fully equipped for such work, while I had furnished all the information in my possession, how and where I had grappled number one, and what measures I should adopt to secure number two. As far as I could, I aided in every way. Among other things I advised steaming across the line of the cable from east to west, for I had towed the broken ends of number one to the westward, leaving the eastern approach clear. Any cable picked up to the eastward would, therefore, in all probability be a live cable.
"Provided thus with all the counsel and knowledge at my disposal, the cable steamer under the Signal Corps, made one last and dramatic effort, passing over the line with the Oregon and Texas between her and the batteries. To make a long story short, she went from west to east, and she did not get the cable then or at any other time."
"On the night of June 18, the admiral allowed the St. Louis to try for the remaining cable. Starting in after nightfall and proceeding from east to west she picked up and severed the cable without difficulty or loss of time."
I think there can be no reasonable objection to our including a properly equipped cable ship among the indispensable auxiliaries to a fleet or to our insisting that she should be of the navy, under naval control absolutely—and not like the Adria, for example, a chartered foreign steamer under the control of a staff officer of the War Department in Washington. Captain Squier, U. S. A., is quite right when he claims that "it may be said at present that no modern fleet is complete without a cable ship especially designed for cable operations in time of war."
I cannot leave the subject of cable cutting without making the suggestion that the other side of the medal ought to receive attention from the naval authorities in general and the General Staff in particular, in order that some provision or arrangement may be made in time of peace for the laying of such cables as are thought or found desirable in putting the plan of campaign into actual operation. Only half our work is done when we interrupt the enemy's communications—we must keep our own intact, and we must supply such missing links or such ramifications of the existing network of commercial cables as will serve to maintain our commander-in-chief in touch with the outside world, should he so desire. If he prefers, like Dewey, at Manila, to drop a veil behind him, cut himself from his base and work along his own path unhampered by instructions from Washington, that is assuredly the prerogative of his high office. On the other hand, if he thinks it wise to follow the example of modern generals with their field telegraph companies and organization, then he should have at his command, vessels for laying submarine cables either of the special design in universal employment by the great corporations, or improvised craft fitted in a rough manner with suitable instruments and provided with sufficient wire stout enough to stand the unavoidable strains, and yet slight enough to occupy small space in the hold. Obviously, a wire for temporary use may, properly, vary in many respects from the established pattern evolved for permanent use on well-known routes. Such a cable would naturally, be so run out as to escape ready detection by the enemy and its starting point would call for adequate defence. It seems to me that the utmost simplicity is sine qua non in all parts of this temporary installation.
Thus, from the desirability of severing our enemy's lines and of maintaining our own communications, the double need arises for the cable ship alluded to above. I think you will all agree with me that she will come when the clouds of war next gather on our horizon and that when she comes she will come to stay.