[Sidenote: Progressive times of high-water.]
The progressive times of high-water, at intermediate points between the Bell Rock and the port of Alloa in the Firth of Forth, appear to follow the same general law, as the great wave of the German Ocean in its progress from the Orkneys southward. These observations on the tides of the Forth apply equally to the Firth and River of Tay, and indeed to all the tributary streams and arms of the sea which communicate with the German Ocean, according to their local situations and magnitudes.
[Sidenote: Tides of the Mediterranean and Baltic Seas.]
If due allowance be made for the peculiar situation and circumstances of the Mediterranean and Baltic seas, it is apprehended, from all that we have been able to learn of the operation of the currents at the Strait of Gibraltar, and Sound of the Cattigate, that these seas are supplied and discharged by in and off shore tides or currents, under certain modifications, and making due allowance for local circumstances, in the same manner as on all other parts of the coast.
I have been thus particular relative to the in-shore and off-shore tides, because they appear in a very puzzling form to the mariner, while writers on the theory of the tides are almost silent on this subject.
DANGEROUS POSITION OF THE BELL ROCK.--SIR ALEXANDER COCHRANE’s LETTER TO THE LIGHT-HOUSE BOARD.--DESIGNS FOR THE BELL ROCK LIGHT-HOUSE.--BILL BY LORD ADVOCATE HOPE IN 1803.--REPORT OF TRADERS OF LEITH.--RESOLUTION OF THE LIGHT-HOUSE BOARD TO APPLY AGAIN TO PARLIAMENT.--MEMORIAL TO THE BOARD OF TRADE.--BILL BY LORD ADVOCATE ERSKINE.--REPORT OF THE COMMITTEE OF THE HOUSE OF COMMONS.--THE BILL PASSED.
[Sidenote: Dangerous Position of the Bell Rock.]
Whatever may have been the early state of the Inch Cape or Bell Rock, as an Island, its present character is strictly that of a sunken rock; and, as such, its relative situation on the eastern shores of Great Britain has long rendered it one of the chief impediments to the free navigation of that coast. It is almost unnecessary to remark, that there are only three great inlets or estuaries upon this coast, to which the mariner steers, when overtaken by easterly storms in the North Sea or German Ocean. These are the Humber, and the Friths of Forth and Moray; of which the Firth of Forth is the principal rendezvous. The mouth of the River Thames, excepting in certain narrow and intricate channels, has not a sufficient depth of water, and is so much encumbered with sand-banks, that no vessel can enter it under night, or approach it in bad weather. On the coast and shores in the neighbourhood of the Humber, the land is flat, and defective in those bold and characteristic features which are essential to the situation of an anchorage for ships in bad weather when they cannot keep at sea. The entrance of the Humber is also considerably obstructed with sand-banks, of which the mariner is, if possible, more afraid than of rocks, because more liable to uncertainty, by the shifting of their position, and thereby changing the direction of the accustomed channels. The great places of resort for ships, therefore, in the North Sea, are the Roads of Leith and Cromarty, lying in the Friths of Forth and Moray, as will be seen from Plate III., in both of which we find the natural advantages of an ample entrance, and a coast so strongly marked as to be easily recognised by the mariner. But from the dangerous position of the Bell Rock, his approach to the shores of this coast, prior to the erection of the Light-house there, was liable to the greatest peril and uncertainty.