The Lead Line
The Lead Line
SINCE the coming of the mariners’ compass many centuries ago, navigation has made steady headway. It is now an exact science, and vessels properly equipped with needed instruments and with men able to use them, can, no matter what the winds or seas, or how extended the voyage, be brought safely to their destination.
The instruments used in navigation are, the compass, by which ship’s courses are steered; the sextant by which observations of the sun, moon and stars are taken, and through which the latitude is ascertained; the chronometer by which the longitude is determined; the log, which measures the ship’s speed; the chart on which the ship’s position is daily traced; the barometer which gives the weight of the atmosphere and warning of coming storms; the hydrometer which shows the saltness of the sea; the thermometer which tells the temperature ofthe ocean; and the sounding lead which gives the depth of water and the nature of the bottom over which the ship is sailing.
The compass, the first in importance to the navigator, was known to the Chinese centuries before the Christian era, and was brought to Europe by the renowned Asiatic traveler, Marco Polo, in the latter part of the thirteenth century. And though improved in many ways the property of polarity in the lodestone, still remains the leading essential.
Careful steering, and good charts are next to the compass. But while sights and observations, the study of the barometer, thermometer and hydrometer should all be faithfully attended to, the lead line will hold its place as one of the important guides to navigation until something is invented whereby the master mariner can penetrate the fog and clouds that obscure the sun and other celestial objects.
The neglect of taking proper soundings has caused the loss of more ships and lives than can be enumerated.
In days long past the anxious navigator has found relief by resorting to the use of the lead line. The story of St. Paul’s shipwreck tellshow the sailors on his vessel deemed that they drew near to land and that they resorted to the use of the lead and line. “When they had gone a little farther, they sounded again and found fifteen fathoms.”
There are seamen who have followed the sea for years and have had no experience with the lead line or any sounding apparatus. They have been on long voyages where it was not necessary to take soundings. I have sailed from land to land more than six months to reach our port of discharge, and during that time the lead has not been cast. Again, during a trip on a three-masted schooner from La Guayra to Maracaibo, we were using the lead as much as the compass in our navigation, even on this short passage.
Although a sailor may have no experience with the lead still he has a knowledge of its use in soundings. Long before I had ever taken a cast I knew how it should be done. My first experience of the deep-sea lead was on the Bermudan brigExcelsior. We were drawing near to the American coast bound in to New York, when we were enveloped in thick fog. Our captain was a competent navigator, and to makesure of his whereabouts after sailing without the sun or stars for three days, it became necessary for him to seek information from the bottom of the sea. Although there was no danger in getting a cast of the lead, as there was very little wind, still on some occasions I have seen all hands called and sail shortened, involving much labor at the peril of life.
I was once on a large American ship where for a whole night we were standing off the Delaware Capes in an easterly gale, and were forced to use deep-sea lead. At considerable peril and much loss of rest for the crew, the ship was rounded to the wind in the face of a dangerous sea, so as to check her speed. Twice during that night we had to haul up the mainsail and lay the mainyard back. At such a time every man is expected to know his duty. Should the night be as dark as pitch, an able seaman must take the lead, weighing twenty-eight pounds, on the forecastle head. He must see that the small cavity in the lower end is “armed”—filled—with tallow. This reveals the nature of the bottom when the lead is hauled aboard. It may be gravel, sand, mud, but whatever it is, it will aid the master in hisnavigation, as the nature of the bottom of the coast is marked on the chart.
In the meantime others had manned the rail, and starting from the quarter they pass the line along on the outside of the ship, till the end reaches the man on the forecastle head. Here he bends on the end of the line to the lead by reeving the eye splice on the end of the line, through the grummet on the top of the lead, allowing the lead to drop through the eye splice.
All being ready, the man on the forecastle head throws the lead overboard, well to windward, shouting as he does so, “Heave.” The man nearest to him feels the tug on the line, and he then throws what he has in his hand to windward making sure the bight of the line is clear of all eyebolts, and shouts, “Watch, there, watch.” Then the next man as he feels the strain lets go of what he is holding and shouts the signal, “Watch, there, watch,” and so on until the line reaches the leadsman aft. Then if the lead has not struck the bottom he pays out the line and tries to get a sounding. Usually there is an officer aft at the line. He feels that the strain is released and taps the lead two or three times to make sure of hissoundings, and then notes the depth by the marks on the line.
The deep-sea lead is about one hundred and twenty fathoms, the first twenty fathoms of it being sometimes marked like the hand lead of which I shall write later. Beginning at twenty fathoms, there is a small piece of cod line with two knots on it, thirty fathoms, the same with three knots, forty fathoms with four knots, and so on up to one hundred fathoms. Half-way between each there is a strip of leather. The length of the lead itself is not counted in this measurement, so the ship gets the benefit of the depth plus the length of the lead. Usually a small snatchblock is on the mizzen backstay for the purpose of hauling the lead aboard. At night the officer of the watch carries the lead to the binnacle light and then reports to the captain the depth of the cast and the nature of the bottom on the tallow.
I once saved a collection from the bottom of the River Rio de la Plata. It was a curious assortment of bits of shell and teeth of small fish. I have heard old sailors tell of finding rare coins, finger rings and pieces of human bones fastened on the tallow of the deep-sea lead.
It is a doleful sound to hear each man along the rail shouting, “Watch, there, watch!” I once saw the second mate of ship leave the poop, and, running down to the main deck, hustle a fellow along who was slow in getting aft to haul in the lead line. After the lead was aboard he received this warning: “When I say come I want you to run, and when I say run I want you to fly, and when you fly, flap your wings or I’ll make you.” This had a good effect, for before the end of the voyage he lost his easy gait and could “hop light and come a running” as well as any on board.
The hand lead line is between twenty-five and thirty fathoms long, according to the height of vessel from the water, but only the first twenty fathoms are used in sounding. I have seen the planks on the deck of an English square rigger marked for the purpose of measuring a new lead line, but on vessels in which I have sailed this was done with a three-foot rule and a bit of chalk. A good-sized eye is spliced in one end, and after wetting the line it is stretched, measured and then marked. The hand lead line consists of nine marks and eleven deeps. Beginning at two fathoms, a piece of leather withtwo ends is tucked into the strand of the line, at three fathoms there are three ends of leather; at five fathoms a piece of white calico, at seven a piece of red bunting, at ten a strip of leather with a hole in it, at thirteen a piece of blue cloth, at fifteen a piece of white calico, at seventeen a piece of red bunting, and at twenty fathoms a bit of cord with two knots.
On some lead lines instead of white calico or blue cloth, bunting of the same color is used, but for accurate soundings on a dark night, the leadsman can put the mark in his mouth and with his tongue tell whether it is cloth, calico or bunting, or he may by feeling the marks tell the difference if his fingers are not too cold. The fathoms which are not marked are termed “deeps.” They are 1, 4, 6, 8, 9, 11, 12, 14, 16, 18, 19.
If a sailing ship is in thick fog close to land the officer of the watch may call a man aft and have him take a cast of the hand lead, or he may do it himself, but on some ocean steamers and yachts the lead is in constant use on entering and leaving harbor.
On a war vessel as soon as the ship draws near to the channel the leadsman is at his post.He fastens a large canvas apron to the shrouds of the rigging so that it will hold him as he stretches his body well over on the outside of his ship. The apron reaching to his feet, protects him from the water falling from the line. Making fast one end of the line to a shroud he takes hold of the other end about nine feet from the lead, and then swings the lead backward and forward till there is motion enough for him to swing it over his head two or three times. He must then let it go at the right time, so that it will drop close alongside under the bow. By the time the vessel has reached the place where the lead sunk it has had time to reach the bottom. As the line comes up and down under the leadsman he taps the bottom smartly and shouts the depth of water to the officer on the bridge. If he sees the piece of red bunting on the surface of the water he calls out, “By the mark seven.” If it should be some distance from the water, he uses his judgment and calls “A quarter less seven,” or “And a half six,” “And a quarter six.” Perhaps he feels safe in believing the mark seven is a good fathom from the water and calls “By the deep six,” and so on through the nine marks and eleven deeps, he calls the soundingshe receives. Generally the hand lead weighs seven pounds, but when the vessel is going at a good rate of speed a fourteen pound lead is necessary. It requires much practice to become a good leadsman. The starboard leadsman throws the lead with his right hand and the port with his left.
On a certain war vessel we had a seaman who was accustomed to throw the lead from the starboard chains. He was changed to the foretop and his first cast of the lead from the port chains caused a man to go on the sick list for several days. Instead of the lead dropping on the outside of the ship it landed on the starboard side of the forecastle head, falling on the feet of a fireman. It was well the force of the lead was broken by first striking the fish davit or it would have broken the man’s head.
Whenever the apprentices were instructed in casting the lead we took good care to keep out of the way, as there was no telling where the lead would drop, for it might go all over the forecastle head instead of the sea. A good leadsman is a valuable man. A part of the examination a merchant sailor receives when he joins the navy is a cast of the lead.
I recall the first time I saw Lord Kelvin’s (Sir William Thomson,) sounding machine used. I was then on a war vessel. The boatswain’s mate sent me aft to assist the quartermaster in taking a cast of the lead.
This machine consists of about three hundred fathoms of galvanized wire to which is attached a glass tube about fifteen inches long by three quarters of an inch in diameter. This tube contains a secret chemical compound on the principal of the thermometer. To the tube is fastened a rod of small iron called the sinker, which, when sounding takes the tube to the bottom where the density of the water acting on the chemical therein shows when carefully read on the indicator, also attached to the tube, the exact depth of the water.
With the ship going at full speed ahead, the quartermaster, aided by two men to attend the brakes and wind in the wire, it ascertained correctly the depth of one hundred fathoms in less than ten minutes.
The seamen to-day feel kindly disposed to this sounding machine which has removed the hardship of the deep-sea lead, and navigators the world over feel greatly indebted to Lord Kelvin,not only for his sounding machine, but because in many ways he has done more than any other man to advance the science of navigation.