Low tide

“ This termagant humor is said to prevail only at half tides. At low water it is as pacific as any other stream. As the tide rises, it begins to fret; at half tide it rages and roars as if bellowing for more water; but when the tide is full it relapses again into quiet, and for a time seems almost to sleep as soundly as an alderman after dinner. It may be compared to an inveterate hard drinker, who is a peaceable fellow enough when he has no liquor at all, or when he has a skin full, but when half seas over plays the very devil. ”

“ I don't know how the tides are, but if it is high tide now, the top of the opening would be eighteen inches out of water at low tide, for, as you know, the tide only rises about two feet on this coast. In that case a boat would be able to come in and out at low tide, but of course a man wanting to come in or go out could easily dive under at any time. Well, that settles that point for the present. It was a clever plan; any amount of water could flow out in flood time, and yet no one who took the trouble to come behind that ledge of rocks we saw would have any idea that there was an opening. ”

“ It was curved like a scimitar, that rock, and within its curve there slept, when the tide was low, a pool. When the tide rose the waters raged and thundered all around the rock, but when it sank again the still, deep pool remained, unruffled as a mountain tarn and as full of mystery.
Over a tumble of lesser rocks that bounded the pool to shoreward the wary might find a path to the Spear Point Caves; but the path was difficult, and there were few who had ever attempted it. For the quicksand lay like a golden barrier between the outer beach and the rocks that led thither. ”

“ It’s nearly dead low tide’. It’ll be on the flood soon, and by the time them there lads get to Blomidon, there’ll be a flood tide.”
“And how will that be for them?”
“It’ll drift ’em back.”
“In which direction?”
“Wal, sir, it would take a man with a head as long as a hoss, tail and all, to answer that there pint. Lor’ bless you, in this here bay there’s no knowin’ where the tide ‘ll drift a man.”
“If it weren’t for the fog, there’d be no danger,” said Mr. Long, musingly. ”

“ The argument on which we are to base our researches is really founded on a very familiar phenomenon. There is no one who has ever visited the sea-side who is not familiar with that rise and fall of the sea which we call the tide. Twice every twenty-four hours the sea advances on the beach to produce high tide; twice every day the sea again retreats to produce low tide. These tides are not merely confined to the coasts; they penetrate for miles up the courses of rivers; they periodically inundate great estuaries. In a maritime country the tides are of the most profound practical importance ”

“ There was one of these rocks which was wholly covered at high tide, and at low tide only the top of it was to be seen. The space between it and the others was too deep for wading, even at low tide. Indeed, there was deep water all around it. ”

“ The time of greatest flow of an artesian well will occur at low tide in the ocean. This might be accounted for from the fact that when the tide is at its height the moon is also pulling upon the crust of the earth, which would tend to take the pressure off the sand rock which lies one or two thousand feet below the surface and through which the flow of water comes, and thus slacken the flow. When the moon is in position for low tide, the crust of the earth would settle back and thus produce a greater pressure upon the water-bearing rock. ”

“ It follows, therefore, that for spring tides the range and rise are synonymous terms, but at neap tides the range is the total height between high and low water, while the rise is the difference between high water of the neap tide and the mean low water level of spring tides. Neither the total time occupied by the flood and ebb tides nor the rate of the rise and fall are equal, except in the open sea, where there are fewer disturbing conditions. In restricted areas of water the ebb lasts longer than the flood. ”

“ You must understand, then, that all tide takes its rise in the free and open ocean under the action of the moon. No ordinary-sized sea like the North Sea, or even the Mediterranean, is big enough for more than a just appreciable tide to be generated in it. The Pacific, the Atlantic, and the Southern Oceans are the great tidal reservoirs, and in them the tides of the earth are generated as low flat humps of gigantic area, though only a few feet high, oscillating up and down in the period of approximately twelve hours. ”

“ If I might regulate the matter, low tide should always fall at sunset or at dawn. Either is a fitting time, with the old earth at peace and its waters stilled or just waking. And at either time I may satisfy my soul with the unapproachable coloring of the Great Painter. The hot noon is no time for clamming. [7] Then the water glares in your eyes, the sun beats down upon your back. The mud is just mud that stinketh in the nostrils. But when I have the happiness to go clamming at sunset, I am wont to stand and gaze and muse, forgetting my errand until I am sunken to my ankles in the mud. ”

“ The tide rises until it reaches a maximum height, called high tide or high water, and then falls to a minimum level called low tide or low water.
The rate of rise and fall is not uniform. From low water, the tide begins to rise slowly at first, but at an increasing rate until it is about halfway to high water. The rate of rise then decreases until high water is reached, and the rise ceases. ”

“ Sue followed her brother Bunny up on the deck of the Fairy. They were quite a distance out from the dock now, and were drifting farther and farther each minute, for the tide was running out. Sandport Bay connected with the ocean, and twice every day there is a great movement of the water in the ocean, called the tide. The tides make the water high twice each twenty-four hours, and then the tides get low, or run out. The moon and sun are thought to cause the tides, as you will learn when you get a little older and have to study about such things. ”

“ The tide, having been before in our favour, was now against us, and, setting with great strength, drove us near the rocks that front the islands to the northward of Island 40; the wind was however sufficiently strong to enable us to clear the dangerous situation we found ourselves in, but soon afterwards it fell to a light air and we were carried by the tide rapidly towards the low rocky extremity of the islets, which we were nearly thrown upon, when a breeze suddenly sprung up again from the South-East and enabled us to clear this impending danger. ”

“ Apart from peculiarities of their own in normal weather, tides are affected by strong winds and a low barometer, and then the tide tables, with their rise and fall to an inch and their time of high water to a minute, become hopelessly inaccurate. ”

“ The sea is here supposed to cover the whole earth and to assume at each instant a figure of equilibrium, and the tide-generating bodies are supposed to move in the equator. Considering only the action of the sun, he assumes that the figure is an ellipsoid of revolution with its major axis directed towards the sun, and he determines the ellipticity of such an ellipsoid. High solar tide then occurs at noon and midnight, and low-tide at sunrise and sunset. The action of the moon produces a similar ellipsoid, but of greater ellipticity. ”

“ The full beauty of the sunrise is but brief. Already the low lakelike mists we saw last night have risen and spread, and shaken themselves out into masses of summer clouds, which, floating upward, threaten to envelop us upon our vantage-ground. Meanwhile they form a changeful sea below, blotting out the plain, surging up into the valleys with the movement of a billowy tide, attacking the lower heights like the advance-guard of a besieging army, but daring not as yet to invade the cold and solemn solitudes of the snowy Alps. ”

“ There is indeed another way of demonstrating that a condition of the system in which the day has assumed equality with the month must necessarily be one of dynamical equilibrium. We have shown that the energy which the tides demand is derived not from the mere fact that there are high tides and low tides, but from the circumstance that these tides do rise and fall; that in falling and [125] rising they do produce currents; and it is these currents which generate the friction by which the earth's velocity is slowly abated, its energy wasted, and no doubt ultimately dissipated as heat. ”

“ The tidal information becomes important and must be considered in navigation or in anchoring in waters where the available depth at low water approximates the draft of the vessel. In the general use of coast charts it is also important to observe the effect of the stage of tide on the appearance of many features. Rocks rising some feet above low water may be entirely submerged at high water. In some areas the aspect may be radically changed between high and low water by the baring of extensive shoals or reefs. ”

“ Twice a day the rise and the fall of the tide covers and uncovers plants and animals, fixed and moving; and through the alternation of spring and neap tides, it results that the exposure of the organisms living low down on the beach, varies both in frequency and duration: while some of them are left dry only once a fortnight for a very short time, others, a little higher up, are left dry during two or three hours at several ebb tides every fortnight. ”

“ It sometimes happens that an unusually high tide occurs. In the port of Dublin, for instance, we have had from time to time exceptionally high water in the Liffey, which has flooded the basement stories of low-lying dwellings. The cause of such extraordinary phenomena is not to be attributed to any unusual development of the strength of the moon's tide-producing capacity, it is rather to be explained in a manner which the tide- predicting engine renders easy to understand. ”

“ It was pleasant and quiet, out there with the sails on the river passing beyond the earthwork, and sometimes, when the tide was low, looking as if they belonged to sunken ships that were still sailing on at the bottom of the water. ”

“ They are very complex, and consist of westward waves and eastward waves of very various periods. He finds, as was to be expected, that if for an ocean of given depth, a free wave very nearly coincides in period with the forced lunar or solar wave, the actual tide is largely augmented. Thus, for example, for an ocean of 29,000 ft. in depth the solar semi-diurnal tide would have a height at the equator 235 times as great as the equilibrium height, and would be inverted so that low water would agree with the high water of the equilibrium theory. ”

“ If, however, the ball is hanging by a long string we can play at battledore and shuttlecock with it, and it always meets our blows. The latter is the analogue of the tides, for a free wave in our shallow canal Tides Inverted. goes slowly, whilst the moon's tide-generating action goes quickly. Hence when the system is left to settle into steady oscillation it is low-water under and opposite to the moon, whilst the forces are such as to tend to make high-water at those times. ”

“ Now I am beginning to live a little, and feel less like a sick oyster at low tide. ”

“ Every improvement of the channel, however, expedites and increases the filling of the river, whilst the volume of water admitted at each tide is further augmented by the additional capacity provided by the greater efflux of the ebb, as indicated by the lowering of the low-water line. ”

“ A rim of the young moon cleft the pale waste of skyline, the rim of a silver hoop embedded in grey sand: and the tide was flowing in fast to the land with a low whisper of her waves, islanding a few last figures in distant pools. ”

“ The kings of the sea."
But, children, at midnight,
When soft the winds blow,
When clear falls the moonlight,
When spring-tides are low;
When sweet airs come seaward
From heaths starred with broom,
And high rocks throw mildly
On the blanched sands a gloom;
Up the still, glistening beaches,
Up the creeks we will hie,
Over banks of bright seaweed
The ebb-tide leaves dry.
We will gaze, from the sand-hills,
At the white sleeping town;
At the church on the hill-side,
And then come back down,
Singing, "There dwells a loved one,
But cruel is she!
She left lonely forever ”

“ It did not check his progress; he was never one to be easily daunted. It was contrary to his very nature to seek shelter in a storm. He went swinging on to the very edge of the quay, and there stood facing the violence of the waves, the fierce turmoil of striving elements.
The tide was extraordinarily high—such a tide as he believed he had never seen before in summer. He stood in the pouring rain and looked first one way, then the other, with a quick birdlike scrutiny, but as far as his eyes could pierce he saw only an empty desolation of waters. ”

“ The tidal movement of the ocean, deep-sea currents, and the agitation of inland waters by the wind, lift up the sands strewn over the bottom by diluvial streams or sent down by mountain torrents, and throw them up on dry land, or deposit them in sheltered bays and nooks of the coast—for the flowing is stronger than the ebbing tide, the affluent than the refluent wave. ”

“ BEAUMONT QUAY
In May, when the sea-birds are hatching their young, the spring-tides are slack and do not cover the saltings. In a pretty figure of speech the fishermen call these tides the Bird Tides.
The lives of the fishermen are ruled by the tides. For them the working hours of the clock have no significance. On the first of the ebb, be it night or day, their work begins, and it is on the flood that they return to their homes. They have no leisure or liking for the time-devouring practice of sailing over a foul tide. The tide in the affairs of these men is absolute. ”