Usually it is found on the British coast encrusting rocks exposed at low tides, or on the flat surfaces formed by sandbanks overlying clay, the latter kind of colonies being known locally as "scalps."
ADAM'S BRIDGE, or Rama'S Bridge, a chain of sandbanks extending from the island of Manaar, near the N.W.
Some of the sandbanks are dry; and no part of the shoal has a greater depth than 3 or 4 ft.
As the mouth is choked with sandbanks, goods are disembarked at Mariinsk and carried by train (9 m.) to Alexandrovsk at the head of the Gulf of Tartary.
Its mouth is divided by sandbanks into many channels.
In front of the delta are sandbanks and rocks which prevent the passage of vessels except by a canal, 18 m.
One consequence of this is that the bed of the river just below Hamburg is obstructed by a bar, and still lower down is choked with sandbanks, so that navigation is confined to a relatively narrow channel down the middle of the stream.
The sea immediately east of the town has a considerable depth, but its navigation is impeded by sandbanks and a bar north and west of the town, which can be passed only by vessels drawing not more than 9 ft.
In the dry season, however, it is obstructed by reefs, sandbanks, shallows, snags, trees and floating timber from the "Apostadero" up, so that even canoes find its ascent difficult, while savage hordes along its banks add to the dangers to be encountered.
The navigation of the stream is considerably obstructed by sandbanks, but vessels of 200 tons can unload at the quays, which, with the town and Friarton harbours, lie below the South Inch.
Its coast is studded with low islands and sandbanks, the results of the deposits brought down by the Hwang-ho.
Long narrow sandbanks almost separate Chifunawuli, the western part of the lake, from the main body of water, while the water surface is further diminished by a number of islands.
Through the sandbanks which form its bed there are two main channels into deep water; one, Boston Deeps, is kept open by the waters of the Witham and Welland; the other, Lynn Deeps, gives passage to those of the Nene and the Great Ouse.
Owing to the prevalence of shallows and sandbanks, navigation is difficult.
The direction of the long sandbanks at the river mouths, which project with remarkable uniformity from west to east, shows that the prevailing winds blow from the west and north-west.
Of water in the dry season, but it has many sandbanks and minor difficulties.
In the dry season it has shallows, and is obstructed by sandbanks, a few rapids and granite rocks.
From its Coca branch to the mouth of the Curaray the Napo is full of snags and shelving sandbanks, and throws out numerous canos among jungle-tangled islands, which in the wet season are flooded, giving the river an immense width.
Its rise and fall are rapid and uncertain, and it is shallow and full of sandbanks and snags.
Coffee, gold, mahogany, rubber and cattle are largely exported; and more than half the foreign trade of Nicaragua passes through this port, which has completely superseded the roadstead of Realejo, now partly filled with sandbanks, but from 1550 to 1850 the principal seaport of the country.
The sandbanks have arrested the encroachments of the sea, which submerged a former site of Aldeburgh.
Above Agram the Save is used chiefly for floating rafts of timber; east of Sissek it is navigable by small steamboats, but, despite its great volume, the multitude of its perpetually shifting sandbanks interferes greatly with traffic. Steamers also ply on the Una, the Drave below Barcs, and the Danube.
In width, dotted with islands and sandbanks; the peninsula at the junction is low, swampy, and intersected by numerous channels.
The deep bay between the coasts of Lincolnshire and Norfolk, called the Wash, is full of dangerous sandbanks and silt; the navigable portion off the Lincolnshire coast is known as the Boston Deeps.
In length, the river had a tendency to form islands and sandbanks - its width now varies uniformly from 455 to 487 yds.
Xxxvi.), gave the following graphic description of the state of the Sulina mouth when the commission entered on its labours in 1856: "The entrance to the Sulina branch was a wild open seaboard strewn with wrecks, the hulls and masts of which, sticking out of the submerged sandbanks, gave to mariners the only guide where the deepest channel was to be found.
Below the town the river divides into several branches, among islands and sandbanks, receiving before it enters the sea the Bolderaa river, and expanding towards the east into wider lacustrine basins.
Dredging machines are kept constantly at work, while steamers are stationed near the most dangerous sandbanks to assist vessels that run aground.