DEEP SEA “FISHING”
How Telegraph Cables Are Laid and Repaired.
Broken Ends Found Three Miles Below Surface.
Capt. Trott of Steamer Minia Describes Operation.
Kearsarge Naval Veterans Listen with Interest.
Difficulties and Dangers of the Work Illustrated.
An old sailor and an old soldier were the guests of honor at the meeting of the Kearsarge Association of Naval Veterans last night.
The old sailor was Capt. Samuel Trott of the cable steamship Minia, now in port, who, at the request Of Admiral White, had prepared a lecture on the laying and repairing of cables; and the old soldier was Gen. A.F. Martin, chairman of the board of police.
The latter was not down on the log for a speech, but when he was called upon for a few remarks he made an extempore effort which drew from the old salts such volleys of applause as fairly shook the building. He told of the obligation of the soldiers to the sailors in the late war, and of the value of such paternal societies as the Grand Army and the Kearsarge association.
The principal guest, however, was Capt. Trott, one of the pioneers of cable laying. He has charge of the repairs of seven of the lines of cable now crossing the Atlantic and laid two of them. He has been 21 years in this special service, so he speaks from some little experience. He illustrated his remarks by charts and grapnels and cables, which he brought from his ship to the hall, and when he concluded his lecture the old sailors were ready to admit that although they knew a good deal of what was going on above water they had received some information as to proceedings under it.
Capt. Trott is a member of the Society of Electrical Engineers and a fellow of the Royal Meteorological Society, and because of the peculiar interest in his subject and the standing of the lecturer, as well as because of the educational features which they contain, his remarks are given in full. He spoke as follows:
HOW THE CABLES ARE MADE.
Delicacy of the Monstrous Strands Which Connect Continents.
The subject of marine telegraphy is to me a very dry one, for having been actively engaged in the work for 21 years you will quite understand that it has become somewhat monotonous. There are many who have lectured and written about it, but very few of them have had much practical experience. I therefore, this evening, purpose giving you a few details from a sailor’s point of view.
There are many textbooks published which give a superabundance of technical phraseology and mathematical formula of “how to do it,” but, after a long experience at the work, I have come to the conclusion that the essential requirement is a capacity to understand the nature of the work, and to practically reason out the details of the many difficulties which are constantly presenting themselves, and that the men best qualified for this important work are those who Sir William Thomson (now Lord Kelvin) once figuratively pictured as “living on the edge of a precipice”—their life’s training having taught them to be always alert and ever ready to act with deliberation at a moment’s notice in any emergency.
Need I say that he was speaking of sailors?
It is also stated that the late Sir James Anderson once said “that it required only an educated boatswain to lay telegraph cables.” I am quite aware that the so-called cable engineers argue differently, but surely experience must have taught them otherwise, and that it requires nothing more than a knowledge of “catenary curves” to guard against the many contingencies which may arise in cable laying.
Submarine telegraph cables, as I suppose most present are aware, consist of a copper conductor, covered with an insulating substance. The best known material for submarine purposes is gutta percha. This is all that may be required for the exchange of signals, it may be, through thousands of miles, but in order to protect it from injury it must also be armored, to guard against the thousand and one dangers to which it may be exposed. This armor, or sheathing, as it is technically termed, consists of iron or steel wires and sundry coverings of hemp laid up helically, each layer being well coated with a bituminous compound. The cable as now completed is put into large iron tanks and kept under water, where it remains ready for shipment
The size and weight of cables vary according to the conditions and locality for which they are destined so that, while some shore ends weigh as much as 20 tons per mile, the modern type of deep sea cable weighs only about two tons per mile. (The earlier deep water cables were much lighter.)
During the whole process of manufacture the strictest supervision is exercised and a continuous watch kept on the electrical tests, so as to guard against or detect the slightest fault should any occur in the insulation. After the completion of the cable it is transferred from the factory to the ship, coiled in her tanks, and again immersed in water, in order to keep a perfect check on its electrical condition. The ship then proceeds to the place where the shore end is to be landed. This is done either by raft, a number of boats, or floated on buoys, through the surf to the beach. The end being landed, it is taken into the cable house, the usual tests are applied, and, if in sound electrical condition, the ship proceeds, laying the cable on a route which had been previously plotted on her charts.
The paying out machinery consists of sundry small guiding wheels and a large drum, usually six feet in diameter, around which the cable runs, with brake pullies attached, fitted in such a manner that weights can be easily adjusted and the speed of the cable running out kept under control. A dynamometer also stands between the paying out drum and the stern of the ship to show the strain on the cable as it passes into the sea. The speed of its running out should be a certain percentage greater than the speed of the ship, so that it may conform to any undulations in the bed of the ocean on which It is intended to rest. Some skill and a great deal of attention is required, in order that too much slack on the one hand, and on the other the greater danger of laying it too tight, and thereby suspending it from peak to peak of submarine mountains, may be prevented, and which generally is only discovered after the cables are broken and repairing operations commenced. This is one of the results of laying cables by mathematical formula, rather than by practical common sense. Another danger at the present time is the excessive speed practised by some in cable laying and the small amount of slack inserted.
I have here a Christmas and New Year card; on the back of it is a report of the laying of a new Atlantic cable, in which is the statement in bold type: “The Record in Cable Laying Broken.” This report goes to show that the ship had laid the deep water portion of it at a speed of rather over eight knots. I fail to see why this fact should be advertised far and wide, when it is well known that a high rate of speed in cable laying, in unknown depths, is likely to prove disastrous to the life of any cable. Then why all this furor? Are cable engineers again losing their heads, as some did in the bygone days, when it is said of them “that the cable ship could always be found by following the trail of the soda water and brandy bottles, and that their servants were clothed in silk stockings, breeches and powdered wigs.” The records of laying the early Atlantic cables show that the maximum speed was six knots and that a percentage of from 11 to 13 was allowed for slack. Notwithstanding this precaution, the repair of certain fractures in them has proven beyond a doubt that they were broken through having been suspended over inequalities of the bottom. Last year on two occasions we repaired a cable which had been broken from this cause, although only five years old and laid in a moderate depth of water. (Scientific evidence has at least once been brought in to prove that a convulsion of nature broke certain cables in deep water; but as I repaired those cables. I am quite certain that there was no ground for such an assumption.)
Having given you an idea of what telegraph cables are, and some of the dangers which beset them in their infancy, also that considerable care and watchfulness is required when depositing them in the ocean in order that they may rest continuously on the bottom, 1 will now pass on to the more important pert of my paper, namely, the recovery and care of broken cables. This requires great skill and exactitude, and a perfect knowledge of all the difficulties likely to be met with, and which have always, more or less, to be encountered, so that in making a comparison of the two classes of work, “cable laying” sinks into utter insignificance.
I had now better explain to you the reason why telegraph cables require repairing so often, that ships are constantly kept in commission for that purpose, at a large expense to the companies owning them. I will also give you some idea of the enormous amount of money which has been spent in trying to recover cables in deep water.
There are many causes of interruptions and faults in cables in the north Atlantic, some of which are: Abrasion on rocks and crushing by ice, where lying in shallow water, or when landed in exposed places. Occasionally, also, there are faults made in the insulator by the ravages of marine borers, but the greatest number of breaks with which we have to contend are caused by the fishing schooners dragging their anchors in gales of wind. Generally they know when they hook a cable, and some will then cut away their hawsers to avoid further damage, knowing they will be compensated for their loss by the cable companies; while others do their utmost to heave them to the surface, and in some few cases have hacked them through with an axe.
(Here the speaker exhibited the ends of an important three conductor cable which was cut by the captain and crew of a Minse fishing schooner.)
Such a flagrant piece of vandalism does not often occur, I am glad to say, and to the credit of the vast number of sturdy fishermen who man the large fleets belonging to the state of Massachusetts, I am glad to bear testimony that there is no such case on record against them. The law is very severe in such eases—a state prison offence—and a heavy fine also can be inflicted; and that would be no bar to a suit for damages. (However, that Down East captain escaped the penalties, having been washed overboard and drowned shortly afterward.) I have already alluded to breaks occurring through laying cables too tight, or at too great a speed. These become more frequent as age advances, or oxidation eats away the iron or steel wires and thereby weakens them so that they can no logger sustain their own weight in the suspended parts. Lastly there is the decay and corrosion which takes place in all depths of water, and as the nature of the bottom is continually changing, so also is this corrosion and decay ever varying, and while in places, on good bottom, they are found after 20 years or more immersion practically equal to new, yet there are other places where bottom is bad, or where they may have been suspended, that the iron or steel wires are completely eaten away only a few hours after being laid.
Another great danger to cables has arisen of late years. I allude to the practice of laying them across the Atlantic between those already laid, and which had previously been considered only a safe distance from each other-30 miles being taken as the minimum in deep water. When it is taken into account that the different ships laying cables may have run for several consecutive days without obtaining a single observation, we may be sure that there is a great chance of some of them being overlaid, or so dangerously near to each other that there will be a great risk of breaking a wrong cable when repairing operations commence; and which must assuredly come in the near future. Beside lying parallel to each other, there are also many places where they cross, four repairs having been already made at these crossings (another is now in progress) with a loss to the companies interested of hundreds of miles of cable, which had to be abandoned in order to avoid the risk of breaking the others.
Is it a strange coincidence that some cables have already been broken soon after repairing operations commenced? When it is taken into account, also, that this type of cable may be roughly estimated at $1000 per mile, is it not wonderful that the companies which are continually suffering such losses do not take steps to recover compensation and prevent this baneful practice in the future?
Let me now refer you to charts showing the positions of the telegraph cables, as given by the companies which laid them. I am sure you will not then be surprised at what has been stated, and that there is a day of reckoning.
From what has already been said you may infer that submarine telegraph cables have only a precarious existence, which is more or less true. Therefore, every precaution should be taken by those laying them to guard against impending dangers; for when breaks occur in deep water, the cost of repairs often amounts to fabulous sums.
Two of the first cables laid in the Atlantic lived about seven and ten years respectively, when they were broken in deep water. Two attempts were made to repair one, and one attempt was made to repair the other. These three expeditions cost in the aggregate about $1,000,000; both cables were then abandoned. A few years later a fault was cut out of another cable in mid-Atlantic at a cost of $400,000. Such enormous expenses and repeated failures forced the managing director of the Anglo-American Telegraph Company to look for some more certain and expeditious means of getting his deep water repairs effected, so toward the end of the year he decided to equip the Minia for this important work (she hitherto having been fitted for shallow water only.) Time has fully proved the wisdom of that decision, her record since then being without parallel in the annals of submarine telegraphy, having accomplished about l20 repairs in the last 10 years (and not a single failure to record against her), although many of them were in the deepest water of the Atlantic, the last of which reaching the enormous depth of 2597 fathoms. This may be considered the Minia’s greatest achievement, for not only did she have many unforeseen difficulties, which seemed almost insurmountable, to contend with, but there was the fact that another ship, nearly double her size, had the previous summer spent the greater part of four months in the attempt and had failed.
There has also during last year been another failure to record by a still larger ship (claimed to be the best equipped for this work of any in existence). Nearly four months were consumed in fruitless efforts. The expense of these two failures may be estimated at not less than $300,000 for ships alone, in addition to which must be added the cost of cable required to replace that which bad been destroyed by hacking it to pieces, in the continued efforts to recover it.
REPAIRING BROKEN CABLES.
The Work of “Fishing” for Fractures in Three Miles of Water.
I will now proceed to explain some of the methods of repairing broken cables. When a break occurs, or a fault develops, the first step to be taken is to locate the position of the said break, or fault, as the case may be. This is done by electrical tests taken from the stations at either end. In order to make this clear, it is perhaps necessary to add a little more to what has already been said regarding its manufacture. The copper conductor consists of a strand of wires of a certain weight per nautical mile. This strand is then covered with a sufficient quantity of gutta percha, put on in several layers; when this is completed it is called the “core.” It is then immersed, at least 24 hours, in water; as nearly as practicable at a temperature of 75 degrees Fahrenheit. The usual tests are then taken.
The coils of core are generally made in lengths of from one to two miles (nautical) and after passing the guaranteed tests they are numbered, labelled and registered, and a record is kept of the portion of the cable into which each length is placed.
The unit of electrical measurements (as most of you are aware) is called an “ohm,” and each nautical mile of this core will have a resistance of so many ohms. We will then suppose that we have a cable of 2000 nautical miles in length, and that the copper conductor has a resistance of three ohms per mile; the total resistance of the whole would be 6000 ohms. Then should our cable be broken, and that from the western station the electrical tests gave a resistance of 2550 ohms, and from the eastern Staten 3450 ohms, we should then have the break located at 850 nautical miles from the west station and 1150 nautical miles from the east station. Such a break as described would have a fair amount of copper conductor exposed at each of the broken ends and would be very easy to locate; but sometimes we have to deal with fractures, which, from their peculiar nature, may have one or even both of the ends partially sealed and offering so much resistance to the escape of current to earth, that although the break may be only a few miles distant, the electrical measurement may be greater than the resistance of the whole cable. You will therefore see that while in some cases a break or fault may be easily located, there are others requiring all the skill of the expert electrician.
Having located the break in our imaginary cable at 850 miles from its western end, we now refer to a chart showing the line of cable, as given by those aboard the ship when it was laid. On it should be shown not only the position by latitude and longitude every day at noon (and oftener when necessary or convenient), but it should also show the distance run and the number of miles of cable payed out; we can then see in what latitude and longitude the 850 miles found by the electrical test places the fault. Being supplied with the necessary data, the repairing ship (which we will assume is the Minia, because she has far surpassed all others in this work), now proceeds to the position indicated, and if by celestial observations her position is considered good, will at once put down a mark buoy, and having anchored it in a seaman-like manner, it will constitute the basis of operations. Acting on the principle that the greater includes the less, we will assume that this repair is to be made in 2500 or more fathoms of water. We then take a series of soundings to ascertain the accurate depth of water, and to examine as much as possible the nature of the bottom on which we have to work. This preliminary survey will also some times indicate to us very plainly where the broken ends of the cable may be looked for. This, in itself, is an advantage, for I can assure you that cables are not always found where they are represented to be by those who laid them, often from no fault of their own, but solely on account of thick weather and unknown currents. As long as cables were laid at a sufficient distance from each other this was not a matter of vital importance, it being only a question of longer search; but, now that they are so much crowded, it is a different matter altogether, for when I tell you that we have found a cable more than 11 miles out of its line of position you may quite understand that it requires more searching for, besides making the difficulty of repairing it much greater, for, should other cables be in the vicinity, there is the danger spoken of already, of hooking and interrupting a wrong cable, and if this should happen, of course somebody would howl!!!
After obtaining all the knowledge of the bottom necessary for our work, a “distance” is run from the mark-buoy to a position on one side of the line of cable, chosen according to circumstances. (Here a little nautical skill comes in again, which is one of the secrets of success.) Having arrived at a point most suitable for the purpose, the grapnel is lowered, and when a sufficient quantity of rope is out it is dragged along the bottom toward the line of cable, continuing the tow until it is hooked. Of course, you will understand that I am describing the manner in which the work is being done by the Minia. (It is very amusing to us reading about other ships crossing and re-crossing the cable they were grappling for and failing to hook it, which you will see is sometimes the case by referring again to that Christmas card.) When we lower a grapnel and drag it across a cable we are sure that in due course of time it will be hooked, and more than that, for a signal will come up from the depths of the ocean-it may be three miles or more distant-notifying us that it is hooked.
Here is our talking grapnel. It tells us when the cable is hooked. It tells us if the cable is slipping off its prongs. It tells us If the bottom is stony. And we also know when it gets hooked in solid rock, although the indications by the dynamometer might lead one to suppose that it was the cable. The machinery used for lowering and heaving in the grappling rope and cable is very powerful, usually capable of lifting from 12 to 15 tons. A dynamometer indicates the strain on it
Having hooked the cable, we now heave in the rope, the ship meanwhile being kept as nearly as possible over the place where the grapnel is hooked. As the cable is being raised from the bottom it becomes tighter, and the strain on it gradually increases until a limit is reached, beyond which, if we continue heaving, it will be broken. Therefore it is necessary to stop before the strain gets too high. Having previously prepared a large buoy, it is now attached to the rope and carefully lowered into the water, the grappling iron is then slipped from the ship, and the cable is now suspended by the buoy, a considerable distance from the bottom.
The ship is again steamed into position, and a cutting grapnel is lowered to the bottom and towed across the line of cable until it is hooked. By an electric arrangement in this grapnel also it shows when it is in its grip, and by continuing the tow the cable is cut on the bottom; the rope and grapnel are then hove on board. We now return to our cable buoy, which is then slipped and taken on board, and having a free end of cable on one side of the grapnel there is much less strain on the cable, so that it can now be raised with much less difficulty or danger of breaking it, and with proper caution it at last reaches the surface. Often many anxious hours are spent in this operation, every movement of the ship having to be watched, for a sudden jerk while heaving would be almost sure to break it. The rope is now secured, and stoppers are put on the cable, by which it is lifted from the grapnel and taken on board. A leading wire is now connected to its conductor, by which the electrician will attach it to his instruments. He then calls the shore station. With almost breathless silence all wait for the welcome news, “Got the shore,” the mental strain is relieved, an involuntary sigh of relief escapes, and frequently a hearty cheer rings through the whole ship. (Sometimes the report is different, and oh! what a difference.) The electricians now take the usual tests, if the cable is perfect between ship and shore, and no time is lost in joining on new cable from ship tanks, and when the splice is completed she steams ahead, laying new cable wherever necessary. This being done, it is cut and buoyed, and after replacing mark-buoys the ship proceeds to her new position, and in much the same manner operates for the recovery of the other end.
When the other end is recovered, if the electricians find it to be perfect to the other station, the new cable is spliced on, and the ship proceeds laying it until the cable buoy is reached; a rope is then sent away and attached to its moorings, and after slipping the buoy and hoisting it on board we heave in on the rope, and take the end of cable on board; it is then again handed over to the electricians, who now take their last tests to each station; if all is in order the final splice is proceeded with, and when finished the bight of cable is carefully lowered into the sea where it again finds its own resting place on the bed of the ocean. All the mark-buoys are then taken up, and the ship returns to the nearest port to learn from the stations whether or not the cable is working all right, for you must understand that as soon as we join the two ends of the copper together we know nothing more of what may take place with the cable until we arrive.
It has more than once happened that when ships returned to port after having been on an important repair that they have learned to their sorrow that the cable was not working, it having broken unknown to them while making their final splice; in such a case the whole operation has to be repeat de novo.
You may have noticed that so far, nothing has been said about the use of boats. It is not, however, because they are not needed, for the boats and the men who man them play a very important part in the work. In fact, the lighting, unmooring and picking up of the buoys 3s the hardest and most dangerous part of this cable repairing business, and it is often done in very bad weather. Our sailors are dexterous boatmen, and whenever called upon for this duty they go without hesitation, knowing that from the ship every care will be taken for their safety. We have an ironclad rule that no boat shall be lowered at sea unless every man has his life belt on, and in bad weather a second boat and crew is always in readiness to be lowered at a moment’s notice, in case anything unforeseen should happen to the other. In this north Atlantic cable repairing the “Minia” has not only the hardest work, but she has also the worst weather to contend with, but I will venture to say that her crew are the finest lot of men that can be found in any ship for this work, being strong, hearty and reliable. Many of them have sailed in her longer than myself, which is now 15 years. All this speaks well for the men and the company they serve.
THE ANGLO-AMERICAN COMPANY.
A Word About Its Inception and the Position It Holds Today.
Before closing this lecture I am prompted to say a little about the Anglo-American Telegraph Company, to whom “Minia” belongs, for I find that in this city the old Pioneer company is hardly known. This may partly be explained by the fact that the Western Union Telegraph Company distributes all our traffic on this continent, except in New York city, where, for several years past, our company has established their own offices, and partly also because in this company we are all so modest that we remain silent, while the officers of the opposition company are continually advertising themselves as the only people who have done anything for the public since submarine telegraphy came into existence. Here’s the way they do it:
“We greet you on the completion of the first decade of our active existence. In these 10 years we have accomplished much for the public.”
“We have made the cable service what it never was before.”
“We have laid a third line across the Atlantic.”
“We have, therefore, made the ‘Commercial’ the speediest and most reliable system between the two continents.”
There are a lot of other “We’s.” They might have summed them up in the one short sentence: We are the only public benefactors!
The Anglo American Telegraph Company, with whom an esteemed American citizen—the late Cyrus W. Field—was connected from its first inception until his death, was established to lay the 1866 cable, and to take over the Atlantic Cable Company’s project, their cable having been lost in deep water the previous summer. It is now a matter of history that the ’66 cable was successfully laid, that it was the first ever opened for traffic between Europe and America, and that shortly after its completion, the ’65 was also recovered in mid-Atlantic, new cable spliced on and continued into Heart’s Content harbor. Thus, in one year, the two great links were completed which were destined to bind together in the closest ties of peace and good will the two great English-speaking nations. Since that time our company has successfully laid not merely a third, but a seventh line across the Atlantic, the last of which has a copper conductor of 650 pounds to the nautical mile, and probably 50 per cent. more speed than any other cable crossing the Atlantic. I simply mention this because so much has been claimed and advertised far and wide by the opposition company, most of which, had it been in order here tonight, I would have unravelled. Many of the officers of this opposition company and most of their staff got their knowledge of submarine telegraphy in the old Pioneer service, and they are among our oldest friends. We, therefore, regret that they should have learned so much how to pervert facts since they graduated from this truthful company.
They remind me of a little incident which occurred in my early cable laying experience. It was a dark night, in the winter of 1874, blowing a gale and raining heavily. We had another ship in company. I wished to give instructions to her by flashing signals, and a young Russian was detailed for this service. After a little while I noticed he kept flashing “Repeat,” “Repeat,” to the man signalling from the other ship. I lost patience, and told him the other signals were better than his, and that I could read all that was sent. He replied: “Ah, captain, it is ever so; the egg is more clever than the fowl who lay the egg.”
And now, Mr. President and gentlemen, from what I have told you tonight about the submarine telegraphy, I think you will see that “we” also, know something about this business, and that the old pioneer, the Anglo-American company, is still in advance of all the others.
In conclusion, I trust that, although as I said before, that this subject is to me a very dry one, I hope that I have succeeded in making it interesting to you.
I thank you all for the very kind attention you have given me.
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