Navigable water

“ There no waters are navigable in fact, or at least to any considerable extent, which are not subject to the tide, and from this circumstance tide water and navigable water there signify substantially the same thing. ”

“ Where streams are large enough to be navigable industrial considerations often prevent the utilization of their power, the streams being more serviceable as highways than as sources of power. Other things being equal, it follows that streams are most available for water-power when they are large enough to have a moderately steady flow, and not so large as to be beyond ready control, or to be valuable for purposes of navigation. ”

“ This great ebb and flow of water serves to aid shipbuilding and the launching of vessels as well as to carry the deep water far up into the inlets of the coast and into the mouths of the rivers, making these navigable for crafts of considerable size well into the land or up to the lowest falls of the streams. ”

“ Water gave us our over-sea commerce, that came in and went out by way of our tidal rivers; and the step proposed toward the fostering of our home industries was a great one when it occurred to somebody to imitate nature, by erecting artificial rivers that should flow whereever we wished them to flow, and should be navigable along their whole course for capacious, flat-bottomed carrying-boats. ”

“ Docking a vessel at a marina on a navigable waterway is a common, if not indispensable, maritime activity. At such a marina, vessels are stored for an extended period, docked to obtain fuel or supplies, and moved into and out of navigation. Indeed, most maritime voyages begin and end with the docking of the craft at a marina. We therefore conclude that, just as navigation, storing and maintaining a vessel at a marina on a navigable waterway is substantially related to traditional maritime activity. ”

“ It is not easy to describe the labour of such navigation. We must prevent the waves from dashing the boats against the cliffs. Sometimes, where the river is swift, we must put a bight of rope about a rock, to prevent her being snatched from us by a wave; but where the plunge is too great, or the chute too swift, we must let her leap, and catch her below, or the undertow will drag her under the falling water, and she sinks. ”

“ Vessels, and other bodies, which have been sunk in the ocean, have been sometimes raised by means of airtight sacks, attached to different parts of the object by means of diving bells, been inflated with air, forced down through hollow tubes by pumps, till they thus acquired a buoyancy sufficient for the purpose. The power of buoyancy has also been applied for elevating vessels above water, by placing hollow trunks, filled with water, under the keel of the vessel, and then pumping them out. ”

“ Thus the effect of currents and wave motion, and the maintenance of trim and equilibrium are not factors in the successful navigation of the vessel; in fact, navigation becomes surer on the surface, as one is travelling in a medium which does not constantly change like the surface water from the effects of winds, waves, and currents. When the divers desire to leave the vessel they go into the diver’s compartment, located in the forward portion of the ship, and close the door communicating with the living quarters. ”

“ The facility for watering ships is good: a reservoir, holding about 200 tons of water, communicates by means of pipes with the end of a jetty, where, even when the tide is out, there is always about three feet of water, which is sufficient for a flat boat to float off ten tons at a time. ”

“ To avoid this waste of our resources it is proposed to add to our navy-yard here a dock within which our present vessels may be laid up dry and under cover from the sun. Under these circumstances experience proves that works of wood will remain scarcely at all affected by time. The great abundance of running water which this situation possesses, at heights far above the level of the tide, if employed as is practiced for lock navigation, furnishes the means for raising and laying up our vessels on a dry and sheltered bed. ”

“ Scarcely a day passes without fresh evidences of the truth of this proposition. The river, as well as the sea-going steamers, are generally built with reference to speed and lightness, coupled with smallness of draft of water, and hence, in case of touching the ground, or of violent storms, it is found that if one portion of the frame gives way, the breaking up of the entire structure follows with a rapidity that is but too well calculated to show the slight manner in which these vessels are constructed. ”

“ Shallow sand-banks and small rocky islands impede the navigation, and it is a common precaution for ships to cast anchor at the least approach of foul weather, an operation which is the more readily set about that the water is nowhere above twenty fathoms, but good holding ground throughout the straits. ”

“ Often, also, he has to saw his way through sheets of ice, cutting out canals with untiring perseverance to gain a piece of clear water beyond. Sometimes his vessel is so tightly frozen within a field of ice that he has no power to extricate her; then the field, urged by the tides or wind, moves on at a rapid rate for hundreds of miles, till it encounters some other field or a projecting shore. ”

“ Wharves and piers are as necessary almost to the successful use of the stream in navigation as the vessels themselves, and are to be considered as an important part of the instrumentalities of this branch of commerce. But to be of any value in this respect they must reach so far into deep water as to enable the vessels used in ordinary navigation to float while they touch them and are lashed to their sides. They must of necessity occupy a part of the stream over which a vessel could float if they were not there. ”

“ In such cases, however, where the rivers flow into tidal seas, it is important to place the jetties sufficiently apart to avoid any loss of tidal influx, since the tidal flow assists the fresh-water discharge in keeping the outlet open; whereas, with rivers flowing into tideless seas, a moderate restriction of the width between the jetties increases the scour. ”

“ When a wooden ship is sailing on a wind, her weather side heaves out of the water a good deal, and, in tropical seas, the sun scorches down on the exposed timber with such merciless effect that, as soon as the vessel is put about and the once-high side is below the water-line, her open seams permit the water literally to pour in, and this keeps all hands busy at the pumps. Moreover, it makes the bilges extraordinarily unpleasant, for the stench of putrefying sea water is about the most stomach-turning odour I know. ”

“ Science might have anticipated, however, that vessels built for fresh-water navigation, and loaded at Lake ports, would have an advantage on the ocean over those loaded on salt water. As is the density of the water of any sea, so is the displacement, or the sinking of the vessel therein. Therefore a vessel can carry a larger cargo in salt water than she can in fresh; and so, a Lake craft, loading at Chicago as deep as she can swim, will find herself, when she reaches the ocean, much more buoyant and lively. ”

“ The stream, which, like nearly all Martial rivers, is wide and shallow, had during the last fifty miles of our course grown narrower, with a depth at the same time constantly lessening, so that some care was required on the part of the pilot to avoid running aground. A stream of twenty inches in depth, affording room for two boats to pass abreast, is considered navigable for vessels only carrying passengers; thirty inches are required to afford a course which for heavy freight is preferable to the road. ”

“ The necessities of river navigation require steamboats and barges to pass through narrow and crooked channels, and to vanture on very shallow water, a water which is constantly varying in its depth, and a channel which often changes its course in a few days very materially. The consequence of this is that both steamboats and barges often get aground temporarily and are soon got off and resume their voyage. Often they rub the bottom of the river for many feet on crossing a sand-bar at low water, and pass on without injury or interruption. ”

“ In some few places the currents caused by the tides are made to do useful work. A large reservoir is filled by the rising tide, and as the water enters it turns a water-wheel. On the ebbing tide the water flows out of the reservoir, and again gives motion to a water-wheel. There is here a source of power, but it is only in very exceptional circumstances that such a contrivance can be worked economically. ”

“ At eleven o'clock in the morning, the air being filled with clouds, we perceived about our vessel, at a quarter of a mile distant, six water-spouts, which made a noise similar to that of water flowing in subterraneous canals, and increased until it resembled the whistling which an impetuous wind makes among the cordage of a ship. We at first observed the water to boil up about a foot and a half above the surface. Above this boiling there appeared a mixed or rather a thick smoke, which formed a kind of canal, that ascended to the clouds. ”

“ Water-born Is when a Ship, even and just with the Ground, first begins to float or swim, being born up by the Water. Water Line Is that which goes round the Ship at the Surface of the Water, and shews the true Shape of her Body. Water Shot Is a Sort of riding at Anchor, when a Ship is moared neither a-cross the Tide, nor right up and down, but betwixt both. Water ways Is that Strake of Plank on the Flat of each Deck respectively next the Ship's Side, for turning the Water out of the Seams. ”

“ A large circular float containing air-valves, and attached to a long hose, was loosened from its fastenings on the deck. The water cylinders were opened, and as they partially filled, the vessel lost its superiority of displacement and began to sink; the large float, with its air-valves, and attached to the hose, remained upon the top of the water, permitting air to be drawn down into the vessel by suction. Thus a constant supply of fresh air was obtained without recourse to the compressed air in store. ”

“ Water is plentiful and of an excellent quality; a stream is brought by pipes to the extremity of the wharf, where two boats may fill with [Pg 187] hoses at the same time, but as the run of water which supplies it is frequently diverted to other purposes by the inhabitants, it is rather a tedious mode of watering, and better calculated for keeping up the daily consumption after being once completed, than for supplying the wants of a squadron or ship arriving from a voyage. ”

“ When we contrast those of early navigators with ships of modern times, among the many alterations, none seems more striking than the difference of their depth. The draught of water that was required for a ship of 300 tons burden would hardly be found enough to float a modern built vessel of 100 tons.250 This alteration in the construction of ships, which is mainly calculated to improve their sailing, by giving them a better hold of the water, seems gradually to have advanced, as the mariner became more adventurous in his voyages ”

“ Gryde proceeded. “The ship is steering by the chart, as these people think, a degree or so to the south of the reef. As you know perfectly well, we are steering right on to it. When you feel the first shock, you will know exactly what to do. That water balance must be shifted as arranged to convey the idea that the vessel is filling, and thus increase the confusion. This course will also lighten the ship by the head, and enable her to float.” ”

“ With a large harbour and the adoption of a detached breakwater, it is possible to gain the advantage of two entrances facing different quarters, as effected at Dover and Colombo, which enables vessels to select their entrance according to the state of the wind and weather; where there is a large tidal rise they reduce the current through the entrances, and they may, under favourable conditions, create a circulation of the water in the harbour, tending to check the deposit of silt. ”

“ One very curious illustration of how such waves may seriously affect a vessel is in that of a yacht built many years ago by an eminent firm on the Clyde, which failed to come anywhere near the performances guaranteed owing to the fact that as the speed increased the hollow following the wave formed at the bow increased and approached nearer and nearer to the paddle-wheels, until the water dropped below the floats and allowed the wheels to spin in the air ”

“ Tide is the vertical rise and fall of the water, and tidal current is the horizontal flow. The tide rises and falls, the tidal current floods and ebbs. The navigator is concerned with the amount and time of the tide, as it affects access to shallow ports. The navigator is concerned with the time, speed, and direction of the tidal current, as it will affect his ship’s position, speed, and course. ”

“ The water is generally deep enough everywhere, too deep in most places for anchorage, and, the winds shifting hither and thither or dying away altogether, the ships, getting no direction from their helms, are carried back and forth or are caught in some eddy where two currents meet and whirled round and round to the dismay of the sailors, like a chip in a river whirlpool. ”

“ Such a tide is of considerable advantage to sailors, since it makes the estuaries both fuller and more spacious, frequently swelling them to a breadth of eight1047 stadia, so that the whole land, so to speak, is rendered navigable, thus giving wonderful facility both for the export and import of merchandise. Nevertheless there is some inconvenience. For in the navigation of the rivers, the sailors run considerable danger both in ascending and descending, owing to the violence with which the flood-tide encounters the current of the stream as it flows down. ”