The ancients believed that the communication be tween the Black Sea and the Mediterranean, and the consequent diminution of the waters of the former, was effected by the bursting of the Thracian Bos phorus, at the period of the deluge which inundated Greece ; and this tradition is confirmed by a refe rence to existing natural phenomena. The cliffs and hills at the mouth of the Bosphorus, are composed of enormous pebbles, which appear to have under gone the action of fire, and afterwards to have been rounded by long contact in water. On the points of , the European light-house, there are immense rocks • of hard and compact lava; and the rock of which the Cyanean Isles consist, appears to have been more or less modified by fire, and to have been cemented during the boiling of a volcano. On the Asiatic side of the strait, a little to the east of the Anatolian light-house, there is a range of basaltic pillars, exhi biting very regular prismatic forms. From the con sideration of all these observations, and comparing events recorded in history with the phenomena of nature, Dr Clarke considers it more than a conjectu ral position, " that the bursting of the Thracian Bos phorus, the deluge mentioned by Diodorus Siculus, and the draining of the waters, which once united • the Black Sea to the Caspian, and covered the great oriental plain of Tartary, were all the consequence of earthquakes caused by subterranean fires, de scribed as still burning at the time of the Ms of the Argonauts, and whose effects are even at this how." (1. 680.) It is proper to mention, that Olivier does not coincide with other naturalists respecting the former extent of the Black Sea, or the bursting of the Thracian Bosphorus.
The north and west coasts of this sea have un dergone, and are still undergoing, considerable changes : the southern coast, consisting chiefly of calcareous rocks, is nearly in the same state in which it was in the time of the ancients. Accord ing to Valerius Flaccus, the gulfs and bays in the north and west coasts were extremely deep ; most of these are now all either entirely filled up, or much contracted. In proof that the Black Sea and the Sea of Azoph are still sustaining a diminution of their waters, it may be stated, that ships which formerly sailed to Taganrock and the mouths of the Don, are now unable to approach either the one or the other ; that the Sea of Azoph has become so shallow, that, during certain winds, a passage may be effected by land from Taganrock to Azoph, through the bed of the sea ; and that the isthmus connecting the Cyanean Isles with the Continent, which does not appear to have existed in the time of Strabo, appears to be increasing. On the south .
ern coast of the Black Sea, there is, as far as we know, only one instance of a recession of the waters: the channel which formerly divided the village of Amasrah, Amastria, is now filled up, and forms a low isthmus.
A rapid current, which generally flows at the rate of a league an hour, the influence of which Is felt at the distance of ten miles from land, when it be gins to take another direction, sets from the Black Sea into the Bosphorus. Sometimes, however, the long continuance of a strong south-west wind effec tually counteracts this current. The Black Sea, from its particular form, being like a basin, into which many large rivers pour their streams, is full of currents, particularly in summer, when the rivers are increased by the melting of the snows when strong winds act against these currents, a high sea is produced. North-east winds prevail from
June to August inclusive ; the most prevalent winds, at other seasons of the year, are from the south and south-west. The general climate of the Black Sea is cold and humid ' • the winters are long and frequently very severe, but the navigation is free of impediment from ice till the beginning of No vember, and often much later. The quantity of fresh water conveyed into this sea renders it brack ish, and liable to freeze with a moderate degree of cold. It is calculated by some authors, particularly Tournefort (II. 404), and the Abbe Barthelemy ( Voyage d' Anacharse Tom. I. c. 1), that what it re ceives is much more ;hen what it discharges into the . Mediterranean. Dr Clarke, however, is of opinion, that the rivers which fall into the Black iea and the Sea of Azoph, do not communicate more water than flows through the canal of Constantinople ; hence he con cludes, that, admitting the effect of evaporation, the level of the Black Sea insensibly falls (I. 648).
The Black Sea receives a considerable portion of the fresh waters of Europe, as well as of Asia Minor. The Danube collects the waters of a great part of Germany, Hungary, Bosnia, Servia, &c. The Dniester, Bog, Don, and Dnieper, discharge into it those of' a part of Russia and Poland. The Phasis collects those of Mingrelia ; and the San garis, and Kisil Irmak, Help, part of those of Anatolia.
In the Black Sea are found the tunny fish, which enters it to spawn ; sturgeon, sterlet, porpoise, mac kerel, soal, turbot, whiting, &c. It abounds with a species of sea-worm, four or five inches long ; its head is like an arrow, and its body consists of a whitish mucilage : these worms are very destructive to ships.
We shall begin our survey of the coasts and ports of this sea, at its entrance from the Bosphorus, and proceed along its western shores. Off each point of the entrance of the Bosphorus from the Black Sea is a group of rocky islets, which retain their ancient name, Cyanean Islands. These have been already described. From the Bosphorus to Kara Kerman, which lies within a few miles of the south ernmost branch of the Danube, the coast is lined by the mountainous ridge of Balkan, Hamm, which terminates at Cape Emeniah, Band extrema. The valleys between these mountains form little coves, where vessels are laden with the timber of Hiemus for Constantinople. The forest of Belgrad, which takes its name from a village near Constantinople, extends along the south-west corner of the Black Sea, for about 100 miles. Incada, Thenias, lies on this coast in 41° 52' north latitude. On the north side of the harbour there is good anchorage ; it is only exposed to winds from the east and south-east, and is sufficiently spacious to contain a fleet ; a heavy sea, however, enters it, when those winds blow to which it is exposed : Its chief export is charcoal to Constantinople. At the head of the Gulf of Foros, which is bounded on the south by Cape Emeniah, is four or five leagues wide, and runs into the land nearly the same distance, is Burgos, which exports a considerable quantity of wool, iron, corn, butter, cheese, &c. to Constantinople. There are several roads ' ads in this gulf fit for the largest ships.