The basin of the Black Sea is of an irregular ovate form, its long diameter lying nearly E. and W. Its greatest length, from the head of the Bay of Burghaz in Rumilia on the west to the boundary between Transcaucasia and Asiatic Turkey near Batum on the east, is about 720 miles. Its greatest breadth is in its western portion, between the estuary of the Dnieper on the north and the mouth of the Sakaria on the south, where it is 380 miles; its middle portion is narrowed, by the projection of the Crimean peninsula on the north and of the coast line of Anatolia between Cape Kerempe and Sinope on the south, to 160 miles; but further east it widens out again between the Strait of Kertch on the north and the mouth of the Kizil Irmak (the ancient Halys) on the south, to 260 miles. Its total area, including the Sea of Azoff, is about 172,500 square miles. The western coast line of the Black Sea, for some distance northwards from the Bosphorus, is high and rocky, having ranges of hills at its back; and the water rapidly deepens to from 30 to 40 fathoms. Between their northern extremity and the range of the Balkans (the ancient Hoemus), which extends east and west, terminating in Cape Emineh, there is a large bay, named after the town of Burghaz at the head of it, which affords a safe anchorage for large ships, the only one on this coast. Between Cape Emineh and Varna the coast line is again low and the shore shallow; and the same condition extends, with but little interruption, along the low-lying region called the Dobrudscha, which extends to the mouth of the Danube. This great river discharges itself by seven mouths, among swampy islands and shifting banks; and the quantity of detritus brought down by it is so large as not only to form a very extensive bar, but also to require the con tinual use of artificial means for its removal from the bel of the navigable channels. The same low coast-line continues along the southern boundary of the Russian steppes, to the shallow inlet which forms the estuary of the Dniester, and of which the mouth is nearly closed by a bar; beyond which, towards Odessa, the coast-line is more lofty, and the waters deepen more rapidly, so that it has been possible to construct a harbour in which ships of considerable tonnage can lie securely. Between Odessa and the mouth of the Dniester the shore again becomes low, and the water shallow; and the outlet of that river, which also receives the River Bog or Bug, is a long shallow bay bordered by shifting sand-banks, which is called the Gulf of Leman or the Bay of Kherson. Only ships of light draught of water can navigate these rivers, of which the Bug is the deeper; and vessels of war, which are built and repaired at the arsenals of Kherson and Nicolaieff, are artificially floated up and down. The Crimean peninsula is separated from the mainland on the western side by the Gulf of Perekop, the northern boundary of which is formed by a narrow belt of sand that runs nearly straight for a distance of 80 miles, and was celebrated by ancient geographers as the δρόμος Άχιλλέως. The inner portion of this gulf is so shallow that only vessels of very light draught can make their way to Perekop, which is situated on the narrow isthmus that divides it from the Sea of Azoff. Along the western coast of the Crimea, however, the coast-line gradually rises, and the shore deepens more rapidly; and’at Eupatoria there is a good harbour for ships of moderate size South of Eupatoria, the coast is formed by cliffs, sometimes of considerable height; and the water is deep almost to their base. The harbour of Sebastopol somewhat resembles that of Valetta in being a deep inlet, subdividing into several branches, in any one of which the largest vessels may find good anchorage, and lie within a cable’s length of the shore. Between Sebastopol and Cape Chersonese are six other bays running inland parallel to each other; and on rounding this we arrive at the harbour of Balaclava, which is a remarkable inlet, having a very narrow entrance, and almost entirely surrounded by lofty heights. Eastward from Balaclava there commences an almost continuous chain of lofty cliffs, with mountains behind them, whose height ranges from 4000 to 5800 feet; the commencement of this chain is formed by Cape Aia or Tarchanskoi, probably the Parthenium of Strabo, the most remarkable headland in the Crimea. Along the whole south-east coast of the Crimean peninsula the water is deep; but there is no good harbour between Balaclava and the Bay of Kaffa, which furnishes an excellent and sheltered anchorage for large vessels, and was formerly much frequented when Kaffa or Theodosia (an ancient Greek colony) was a port of considerable importance. The peninsula of Kertch and the island of Taman, which separate the Sea of Azoff from the Black Sea, are for the most part low and sandy, the most elevated land in each being near the border of the Strait of Yenikale. On the western side of this strait the town of Kertch is situated, upon what was formerly known as the Hill of Mithridates.

The Sea of Azoff may be considered as the wide shallow estuary of the Kiver Don, which discharges its waters into the north-eastern prolongation of the sea, sometimes distinguished as the Gulf of Taganrog; its area is estimated at about 14,000 square miles; and its depth, which is nowhere more than 7⅛ fathoms, diminishes near the shores to 4⅛ fathoms, and is less than 2 fathoms opposite the town of Taganrog. These depths show a tendency to yet further diminution through the deposit of river detritus,— vessels which could formerly pass up the gulf as far as Taganrog being no longer able to do so, whilst during certain winds the bottom becomes dry enough to be crossed between Taganrog and Azoff. The western portion of this basin is separated from the rest by a long narrow strip of low sandy land, enclosing what was named by the Greeks the Putrid Sea,—into which, when the wind is easterly, the water of the Sea of Azoff passes through a narrow opening at the northern extremity of the bar, but which at other times consists of a series of swamps and quagmires, equally impassable to men and animals, and giving fortlι noxious exhalations that render the adjacent country nearly uninhabitable. The water of the Sea of Azoff is always less salt than that of the Black Sea; and when the Don is at its fullest, the large quantity of fresh water which is mingled with the water of the sea renders the latter nearly drinkable, and tends to empty the basin of its salt. When, on the other hand, the river brings down but little water, and the wind is from the south, there is a considerable reflux of the more saline water outside; and thus the average salinity of the water of the Sea of Azoff is maintained,—just as is seen to be the case on a larger scale with the Baltic. See Baltic, p. 297.

The whole of the portion of South Russia that lies between the Dnieper and the Don is an almost unbroken steppe, but very little elevated above the sea-level; and there are abundant indications of its having been at no remote period covered by salt water. For not only are there numerous salt lakes and marshes at a long distance, inland from the present coast-line, but extensive beds of sea-shells, which have become mineralized into strata of solid limestone, sometimes 30 or 40 feet in thickness. The like features prevail over the plain which lies between the Don and the Kuban, and which forms the eastern boundary of the Sea of Azoff; this plain, inhabited by nomade Kalmucks and Cossacks, extends eastward to the desert of Astrakhan; and as salt marshes and beds of sea-shells are found there also, it is evident not only that both the Black Sea and the Caspian extended farther north than they do at present, but that they were then in continuity with each other over the plain of South Russia, though separated towards the south by the Caucasian Highlands. It is interesting to note that Pliny expressly stated that the Tauric Chersonese was not only surrounded by the sea, but that the sea covered all that northern portion of it which is now an alluvial level.

The island or peninsula of Taman, which forms the eastern border of the Strait of Yenikale, is for the most part an expanse of salt-marshes and lagoons, into which the River Kuban discharges itself,—one portion of its water passing into the Sea of Azoff and the rest into the Black Sea. At Anapa, a little to the east, the Caucasian range comes down to the sea; and thence around the shore of Circassia, the coast-line is high with a mountainous back-ground, and the water rapidly deepens. As the great mountain range trends inland, however, the coast becomes lower; and the region now termed Mingrelia, the ancient Colchis, is a fertile plain, through which run the River Rion (the ancient Phasis) having the important port of Poti at its mouth, and the Khopi, at the mouth of which is Redout Kale. Through these channels the merchants of Tiflis export the produce of the interior, and import European goods. Passing the boundary between Russia and Turkey, the coast -line begins to trend westwards, to the outlet of the large river Chouruk (the ancient Batys), where the fortified town of Batoum is situate at the base of the northern mountain range of Asia Minor. This range extends, with occasional interruptions,' along the whole southern coast of the Black Sea, sending down spurs that form headlands and promontories, sometimes of considerable height. Owing to the steepness of the shores, there are few good anchorages here, except in the Bay of Samsoun, which receives the River Yeshil, and the Bay of Sinope, which receives the Kizil-Irmak,-at the mouths of which rivers there are plains formed by their alluvial deposit. From Cape Injeh westward to the Bosphorus, the coast-line of Anatolia is continuously elevated, with high mountains in the back-ground, occasionally projecting seawards as lofty promontories, of which Cape Kerempe is the most noteworthy; numerous rivulets come down from the mountains, and discharge themselves into little coves; but excepting the Sakaria (the ancient Sangarius), there is no considerable river, and the water deepens very rapidly to 20 fathoms or more.

Although it is known that the depth of the central part of the basin of the Euxine reaches 1070 fathoms, the extent of this deep depression is not known. The increase of depth off the low-lyiug western and north-western shores is very gradual and regular, the lines of 20, 30, and 60 fathoms maintaining a general parallelism to the coast,—so that within this range the distance of a ship from land can be approximately ascertained by sounding. But outside the 60 fathom line the bottom deepens more rapidly and less regularly, depths of from 600 to 700 fathoms being met with in some parts within a few miles of it. The depth of the eastern portion of the basin has not been ascertained, but it is probably considerable.

The basin of the Euxine communicates with that of the Sea of Marmora by the Bosphorus, a strait about 20 miles long, from f to 2∣ miles wide, and a depth of from 30 to 40 fathoms, resembling a broad river with high banks, which maintain a general parallelism, although the strait has seven distinct reaches. The region on either side presents distinct evidence of recent volcanic action.

The Sea of Marmora lies in the course of the channel that connects the Black Sea with the Aegean. Its bottom is depressed to a depth far greater than that of the channel of which it is an expansion. Its length from strait to strait is 110 geographical miles, and its greatest breadth is 43 miles. Round the shores, the depth generallyranges from 10 to 30 fathoms; but it rapidly increases in most parts; and depths of 100, 133, 266, and even 355 fathoms have been met with, chiefly near the line connecting the two straits.

The channel which connects the Sea of Marmora with the Aegean is properly termed the Hellespont,—the name Dardanelles, by which it is commonly known, being really that of the fortifications erected ©n the two sides of the strait by which its passage is guarded. The Sea of Marmora narrows to a breadth of ten miles towards the north-eastern entrance of the channel; at Gallipoli, the distance between the two shores suddenly contracts to about two miles; and between this and the Aegean end of the strait, that distance is further diminished at certain points to even less than a mile. The depth of the channel is considerable, being for the most part between 30 and 50' fathoms.

Climate.— The climate of the Black Sea is very peculiar,— the range of temperature between the summer and winter extremes being remarkably great. The summer isotherm of 70° runs a little way inland, nearly parallel to its northwestern coast-line, whilst the summer isotherm of 80° passes along its southern coast-line, which is as warm as the southern coast-line of the Mediterranean, nearly 10° nearer the equator. Thus the whole area of the Black Sea lies, like that of the Mediterranean, between these two summer isotherms; and the evaporation from its surface during the warmer part of the year will consequently be enormous. During the winter months, on the other hand, the Black Sea is exposed to the chilling winds which come down to it from the Arctic regions, sweeping over the snow-covered plains of Russia, without any interruption from high mountain ranges; and nearly the whole of its area lies between the winter isotherms of 30° and 40°, the former passing round its northern coast, while the latter passes from the Bosphorus to Poti in Mingrelia. Thus it happens that, notwithstanding their high summer temperature, the northern shores of the Black Sea are more or less blockaded with ice during the winter,—this being most the case where the water is shallowest, and has its salinity lowered by the entrance of rivers. Thus the Sea of Azoff and the Strait of Yenekale are always frozen over, as are also the northern ports between the Crimea and Odessa; while, on the other hand, the harbours of Kaffa and Sebastopol are never closed, and that of Odessa but seldom. It is recorded, however, that in 401 a.d. the surface of the Euxine was almost entirely frozen over, and that when the ice broke up enormous masses were seen floating in the Sea of Marmora for thirty days. In 762 a,d., again, the sea is said to have been frozen from the terminal cliffs of the Caucasus to the mouths of the Dniester, Dnieper, and Danube; and contemporary writers assert that the quantity of snow which fell on the ice rose to the height of from 30 to 40 feet, completely hiding the contour of the shores, and that on the breaking up of the ice in the month of February, the masses of it carried by the current into the Sea of Marmora reunited in one immense sheet across the Hellespont between Sestos and Abydos. No similar occurrence has been subsequently recorded.

The winds of the Black Sea are variable, except during summer, when they generally blow from the north-east, while at other seasons southerly or south-westerly winds cften prevail. The area is very subject to fogs, which appear to proceed from the precipitation by a cold northerly current of the moisture which has been raised by evaporation from its surface, or has been brought thither by S. or S.W. winds. This sea is remarkable for the rapidity with which violent storms not unfrequently arise, often to subside again with like rapidity.

Drainage Area.— The drainage area of the Black Sea is one of the largest in the world, being estimated at 939,000 square miles, of which 825,000 lie in Europe and 114,000 in Asia. The largest of its rivers is the Danube, which has a total length of 1560 miles, and drains the immense area of 306,000 square miles in the southern portion of Central Europe; its western tributaries lie so near the southern tributaries of the Rhine and the Elbe, that a canal-communication has been established between them, by which small vessels can pass between the North Sea and the Black Sea. The Dnieper has a total length of 1050 miles, and drains an area of 195,500 square miles, chiefly in Western Russia and Russian Poland; its northern tributaries approach the southern tributaries of the Niemen; and a canal-communication has thus been established between the Black Sea and the Baltic. The Don, with a length of 1000 miles, drains an area of 176,500 square miles in South-Eastern Russia, which is conterminous with the basin of the Volga, being separated from it by the Sarpa Hills. Between the Dneiper ana Danube, the two smaller rivers, the Bug and the Dniester, traverse respectively 440 and 660 miles in their course, and drain an area of more than 50,000 square miles (ten times greater than that of the Thames). Passing eastwards, we come to the Kuban, which drains the northern slopes of the Caucasus and the plains inhabited by the Black Sea Cossacks, and debouches near the entrance to the Sea of Azoff. But there is no other important river on the eastern coast, most of the water flowing from the mountainous region that separates the Black Sea from the Caspian passing into the latter. The northern slopes of the Armenian mountains furnish tributaries of the River Chouruk, a stream of moderate size, which enters the Black Sea to the east of Trebizond. On the southern coast the principal river is the Kizil Irmak (the Hal·ys of the ancients’), which drains the large central area of the northern portion of Asia Minor, while towards the western side the River Sakaria drains a large area in the province of Anatolia. Along the whole western coast of the Black Sea, from the Bosphorus to the Danube, no large stream empties itself into the basin,—most of the drainage of Rumilia being carried off by the River Maritza into the Aegean, whilst that of Bulgaria contributes to swell the Danube.

The greater part of the drainage area of the Black Sea, like that of the Baltic, is covered with snow during the winter months, and comparatively little water is then brought down by the rivers. With the return of spring, however, the melting of the snow increases the volume of fresh water poured into the sea, its rivers being at their highest in early summer. By far the larger part of this water is discharged at its north-western border; and the elevation of level thus produced establishes a current that sets along its western shore towards the outlet of the Bosphorus. But as the narrowness of this...