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Chronicles of Canada Volume 31 - All Afloat: A Chronicle of Craft and Waterways

{82} <h3> CHAPTER VI </h3> <h3> SAILING CRAFT: THE BUILDING OF THE SHIP </h3> Shipbuilding was and is a very complex industry. But only the actual construction can be noticed here, and that only in the briefest general way. The elaborate methods of European naval yards were not in vogue anywhere in Canada, not even in Quebec, much less in Nova Scotia. It was not uncommon for a Bluenose crew to make everything themselves, especially in the smaller kinds of vessels. They would cut the trees, draft the plan, build the ship and sail her: being thus lumbermen, architects, builders, and seamen all in one. The first step in building is to lay the blocks on which the keel itself is laid. These blocks are short, thick timbers, arranged in graduated piles, so that they form an inclined plane of over one in twenty, from which the completed hull can slide slowly into the water, stern first. Then comes the laying of the keel, that part which is to the whole vessel what {83} the backbone is to a man. A false keel is added to the bottom of this in order to increase its depth and consequent grip. This prevents the side drift which is called making leeway. The false keel is only fastened to the keel itself from underneath, because such a fastening is strong enough to resist water pressure and weak enough to allow of detachment in case of grounding. The slight projection of the keel itself then gives too little purchase for a dangerous amount of leverage on the frame. A long keel is made up of several pieces of square timber, with their ends shaped into scarfs, an overlapping and interlocking arrangement of great strength. The foremost keel piece is scarfed into the stem, which is the fore-end of the vessel's bow. The aftermost keel piece joins the stern-post, on which the rudder hangs. Elm makes a good keel, especially with oak for stem and stern-post. The frame, to pursue our simile, is to the ship what ribs are to our bodies. In the same way the planking is the skin. The frame, or ribs, determines the vessel's form. There were, and still are, many varieties of frame. In a very small vessel there are very few timbers. The keel is probably all in one piece, and the planks may possibly run from stem {84} to stern without a break. In this case the unity of each piece supplies enough longitudinal resistance to strains. But when a vessel is large, and more especially when she is long, the strains known as hogging and sagging are apt to rack her timbers apart. A ship is not built for mere passive resistance, like a house, or even for resistance only to pressures and vibrations, like a bridge. She is built to resist every imaginable strain of pitching and rolling, and so requires architectural skill of a far higher kind than is required (in the constructional, not the aesthetic, sense) for any structure on the land. When a ship is on the top of a single wave she tends to hog, because there is much less support for her ends than for her centre, and so her ends dip down, racking her upper and compressing her lower parts amidships. When the seas are shorter she often has her ends much more waterborne than her centre, and this in spite of the fact that the extreme ends are not naturally waterborne themselves. Then she sags, and the strains of racking and compressing are reversed, because her centre tends to sink and her ends to rise. Now, a series of hogging and sagging strains alternately compresses and opens every resisting join in every {85} timber, with the inevitable result of loosening the whole. To meet these strains longitudinal strength must be supplied. The keel supplies much of it, so does the planking (or skin) to a lesser degree; but not enough; and the ribs, by themselves, are for transverse stiffening only. Four means are therefore employed to hold the parts together lengthwise—keelsons, shelf-pieces, fillings, and some form of truss. The keelson is an inverted keel inside the vessel. The floors, which are the timbers uniting the two sides of the frame (or ribs), are given a middle seating on the keel. The keelson is then placed over them, exactly in line with the keel, when bolts as long as the thickness of all three are used to unite the whole in one solid backbone, and this backbone with the ribs. Side or 'sister' keelsons were used in the Navy on either side of the mainmast for a distance equal to about a third of the length of the keelson. But they were little used in merchant vessels, and their longitudinal resistance was only partial and incidental. Shelf-pieces and waterways were adapted from French models by Sir Robert Seppings, who became chief constructor to the Navy some years after Trafalgar. They are thick timbers running continuously under and {86} over the junctions of the deck beams with the ship's sides, to both of which they are securely fastened. The keelson was an old invention and shelf-pieces and waterways were soon in vogue. But fillings and trusses, both expensive improvements, were not much favoured in any mercantile marine. The truss is even older than the keelson, having been used by the ancient Egyptians at least thirty-five centuries ago, and probably earlier. Four to eight pillars rose in crutches from the bottom amidships to about six feet above the gunwale. The Egyptians ran a rope over the crutches and round the mast, and then used its ends to brace up the stem and stern. The moderns discarded the rope, took the strains on connecting timbers, and modified the truss, sometimes out of recognition. But many Canadian and American river steamers of the twentieth century A.D. employ the same principle for the same object as the Egyptians of the seventeenth century B.C. Fillings came from the French, like shelf-pieces and waterways. Seppings put them between the ribs, in the form of thick timbers. The whole frame thus became almost solid against any tendency of the ribs to close together, and quite strong {87} enough against their other tendency to draw apart. All means that strengthen a well-built hull longitudinally have also been made to add their quota to its transverse strength. The ribs spring from the solid mass of their own floors bolted in between the keelson and the keel; and the planking, or skin, is let into the rabbets, or side grooves, of the keel and firmly fastened to the ribs throughout by hardwood pegs called treenails. The decks are, in themselves, a source of weakness. The beams supporting them are like the rafters of a house, which, of course, work the walls apart under pressure from the floors—and here, as in every other detail, the stability required for a house is nothing to what is required for a ship. The way to overcome this difficulty is to make the decks and beams so many bridges holding the sides together. At the point of junction of every beam-end with a shelf-piece, waterway, and rib there is an arrangement of bolts and dowellings (or dovetailings) which makes the whole as solid as possible. An extra bolt through the waterway, rib, and outside planking adds to the strength; and a knee, or angular piece of wood or iron connecting the shelf with the under side of the beam, almost completes the {88} beam-end connection. The final touches are the clamps below the shelves and the spirketing above the waterways, with short-stuff between the clamps of one deck and the spirketing of the next below. All this is only the merest suggestion of what is done for the main part of the vessel's hull. The ends require many modifications, because the shape there approaches a V, and so the floors cannot cross the keel as holding bodies. But the breast-hooks forward and crutches aft, the deck transom, which is the foundation for the deck abaft as well as the assemblage of timbers uniting the stern to the body of the vessel, with all the other parts that make up the ends, cannot be more than mentioned here. Then come the decks, which are quite complex in themselves, and still more complex by reason of the mast-holes and hatchways cut out of them all, and the windlass, bitts, and capstan built into the one that is exposed to the storm. To make sure that whatever strength is taken out by cutting is restored in some other way, and that the exposed deck which has to resist the strains put upon the structures built into it is specially reinforced, the most careful provision must be made for the mast-holes; for the hatchways {89} with their coamings fore and aft on carlings that reach from beam to beam; for the riding bitts, which are posts to hold the cable when the vessel is at anchor, and which must therefore be immensely strong; for the windlass, which in the merchant service often did the double duty of the bitts and capstan; and for a multiplicity of other parts. A landsman could hardly believe what a marvellous adjustment of co-operating parts is required for a ship unless he actually watches its construction. He will then understand why it is by far the most wonderful structure man has ever built throughout all the ages of his evolution. It represents his first success in mastering an element not his own; and, whatever the future may see in the way of aviation, the priority of seamanship will always remain secure by thousands and thousands of known and unknown years. But we are still no farther than a few parts of the hull. There is the stepping of the masts, with their heels set firm and square above the keel, and their rake 'right plim' throughout. Then there is the whole of the rigging—a perfect maze to look at, though an equally perfect device to use; the sails, which require the most highly expert workmanship to make; {90} the rudder, and many other essentials. Finally, there is all that is needed in every well-found vessel which is 'fit to go foreign.' No vessel would go far unless its under-water parts were either sheathed, tarred, or tallowed; for sea-worms burrow alarmingly, and 'whiskers' grow like the obnoxious weeds they are. These particulars, of course, leave many important gaps in the process. Then the hull has to be transferred from the inclined plane of block piles, on which it was built, to a cradle, on which it moves down the sliding-ways into the water. When everything is ready, the christening of the ship takes place. A bottle of wine is broken against her bows and her name is pronounced by some distinguished person in a formula which varies more or less, but which is generally some version of the good old English benediction: 'God bless the Dreadnought and all who sail in her.' No matter what the name may be, the ship herself is always 'she.' Many ingenious and mistaken explanations have been given of this supposedly female 'she.' The schoolboy 'howler' on the subject is well known: 'All ships are "she" except mail boats and men-of-war.' Had this schoolboy known a very little more he might {91} have added jackass brigs to his list of male exceptions. The real explanation may possibly be that the English still spoken at sea is, in some ways, centuries older than the English spoken on land, and that the nautical 'she' comes down to us from the ancient days in which all inanimate objects were endowed with life in everyday speech and neuters were as yet unknown. Immediately this most stirring ceremony ceases, the stentorian order comes to 'Down dog-shore!' on which the dog-shore trigger is touched off, the dog-shores fall, an awakening quiver runs through the sliding-ways and cradle; and then the whole shapely vessel, still facing the land from which she gets her being, moves majestically into the water, where her adventurous life begins. <div style="break-after:column;"></div>

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