The same laws are observable in the rise and fall of the tides at the Bell Rock, as on the opposite and most contiguous shores of Forfarshire. On the days of new and full moon, it is high water at the rock at 40 minutes past one o'clock; The ordinary rise of spring tides is about fifteen feet, and of neap tides nine feet ; but so much depends upon the state of the weather, that the tides vary from one to three feet in the rise and fall bath of spring and neap tides ; so that at low water much less of the rock will appear at one time than at another ; and instead of sliming itself at low water of neap tides, it is sometimes from one to three feet under the surface of the water. Westerly winds have always a tendency to raise the tides' higher, while easterly winds have a contrary effect.. In moderate weather, the course of the flood tide is south-west, and of the ebb-tide north-east, with some little variation, according to the time of tide. Spring tides have a velocity of three miles an hour near the rock, and neap tides about a mile and a quarter.
It is not a little remarkable, that so small a rock should follow the same laws in influencing the cur rent with the coast of a country. Upon the rock it is flood-tide two hours before the ebb ceases to run at the distance of half a mile ; so that the flood-tide will have almost covered the rock, while vessels in the offing are striving with an ebb-tide. The same thing is observable in a greater or less degree, according to the velocity of the tide, along all coasts ; and the ma riner accordingly knows how to shun an adverse tide, and to seek one in his favour, by keeping nearer, or at a greater distance from the shore.
• The lower parts of the rock are covered with fuci, chiefly of the larger sores, as the great tangle, fucus digitalis, and the badderlocks, or hen ware ; which last is found of the length of 18 feet, and must then be very aged, as plants of the first year's growth are but a few inehes long; and in two years they are found to be only about 18 inches in length. The higher parts of the rock abound with smaller fuci ; as F. mamillosus, and F. palmatus, the common dulse ; F. alatus, and F. coccineus, are found on the older stalks of tangle ; and F. subfuscus and confervoides occupy the smaller pools. In some places the rocks are ren dered slippery with ulva compressa, and umbilicalis ; and the higher parts are so thickly covered with con ferva rupestris, as to resemble a sward of grass.
The rock is covered with lepas balanoides, and some parts abound with the common limpet and mus cle ; actinia erassicornis, with star-fishes ; asterias glaeialis, and occulata, are common. Common crabs of a large size, and a few lobsters, are found. Seals frequent the rock at low water, and it then becomes the resort and resting place of cormorants, shags, and herring-gulls, which feed on the haddocks and cod- ' lings found around the rock.
When the building of the light-house was begun, there was not a muscle to be seen upon the rock ; but in less than four years, the north-east part was com pletely covered with muscles of a small size. These
appeared to have been propagated from a few depo sited for a stock of bait for the workmen engaged at the building, who were in the practice of employing their leisure hours in fishing. It is, however, to be feared, that the 'muscles will very soon be extirpated by their natural enemy the white bucky, buceinum lapillus, which seems to be increasing ‘, in proportion to the means of subsistence" ; and is rapidly de stroying the muscle,.by perforating a very small hole with its proboscis, through which the substance of the.muscle is sucked out, when the shell opens, and is washed away by the tide.
From the various depths of water, and the variety of the bottom, which alters as the distance of the I rock and the soundings are increased, from a rocky r bottom, to coral, rough sand, rough gravel, shell sand, fine sand, and mud, which is found in the course of the tide from the Tay. From the circumstance of this variety, the following kinds of fish are caught near the rock in great abundance, and of excellent quality. The red-ware cod, close to the rock ; and at a greater distance, the common cod, ling, liolibut, skate, thornback, plaise, turbot, gurnard, wolfe fish, phod. dog-fish or leacdy,coal-fish, whiting, had dock, flounder, sole, mackerel, and herring.
It is worthy of remark, that when the weather be comes very cold in spring and autumn, and when the sea is agitated much by the wind, the fish appear to leave the vicinity of the rock, and perhaps go into deeper water. Of this, ample proofs have been af forded by the lighthouse vessels riding off the rock at all seasons of the year.
" The Bell Rock is exposed to the wares of the ocean in the directions of north-east, east, and south-east, without any land between it and the continent of Norway and Jutland ; on the opposite points of the compass, it lies open to the shores of Berwick, Had dington, Fife, and Forfar. Relatively to the two last counties, it may be considered as holding a centrical situation in a capacious basin, with a depth of water increasing from the shore till within two miles of the rock, where the ultimate depth is 23 fathoms ; and from thence to the rock the soundings gradually di minish. At low water of spring tides, and at the dis tance of 100 yards from the rock, in all directions, there are about three fathoms water. On the south east side, in the direction of the inclination of tire strata, the water deepens more suddenly to 35 fathoms ; and as you stand out to sea, the soundings become less and less ; and at the distance of 30 miles, the wa ter is only 22 fathoms deep upon Marr's Bank, which appears to be a deposition formed by tire joint-opera tion of the waters of the Forth and Tay, influenced by the great wave of tide which proceeds round tire island.