After the melting of the snow there appears besides a number of inequalities, and the clefts previously covered with a fragile snow-bridge now gape before the wanderer where he goes forward, with their bluish-black abysses, bottomless as far as we can depend on ocular evidence. At some places there are also to be found in the ice extensive shallow depressions, down whose sides innumerable rapid streams flow in beds of azure-blue ice, often of such a volume of water as to form actual rivers. They generally debouch in a lake situated in the middle of the depression. The lake has generally an underground outlet through a grotto-vault of ice several thousands of feet high. At other places a river is to be seen, which has bored itself a hole through the ice-sheet, down which it suddenly disappears with a roar and din which are heard far and wide, and at a little distance from it there is projected from the ice a column of water, which, like a geyser with a large intermittent jet in which the water is mixed with air, rises to a great height.
Now and then a report is heard, resembling that of a cannon shot fired in the interior of the icy mass. It is a new crevasse that has been formed, or if one is near the border of the ice-desert, an ice-block that has fallen down into the sea. For, like, ordinary collections of water, an ice-lake also has its outlet into the sea. These outlets are of three kinds, viz., ice-rapids, in which the thick ice-sheet, split up and broken in pieces, is pressed forward at a comparatively high speed down a narrow steeply-sloping valley, where ice-blocks tumble on each other with a crashing noise and din, and from which true icebergs of giant-like dimensions are projected in hundreds and thousands; broad; slowly-advancing glaciers, which terminate towards the sea with an even perpendicular face, from which now and then considerable ice-blocks, but no true icebergs, fall down; and smaller stationary glaciers, which advance so slowly that the ice in the brim melts away about as fast as the whole mass of ice glides forward, and which thus terminate at the beach not with a perpendicular face but with a long ice-slope covered with clay, sand, and gravel.
The inland-ice on Novaya Zemlya is of too inconsiderable extent to allow of any large icebergs being formed. There are none such accordingly in the Kara Sea[89], and it is seldom that even a large glacier ice-block is to be met with drifting about.
The name ice-house, conferred on the Kara Sea by a famous Russian man of science, did not originate from the large number of icebergs[90], but from the fact that the covering of ice, which during winter, on account of the severity of the cold and the slight salinity of the surface-water, is immensely thick, cannot, though early broken up, be carried away by the marine currents and be scattered over a sea that is open even during winter[91]. Most of the ice formed during winter in the Kara Sea, and perhaps some of that which is drifted down from the Polar basin, is on the contrary heaped by the marine currents against the east coast of Novaya Zemlya, where during early summer it blocks the three sounds which unite the Kara Sea with the Atlantic. It was these ice-conditions which caused the failure of all the older north-east voyages and gave to the Kara Sea its bad report and name of ice-house. Now we know that it is not so dangerous in this respect as it was formerly believed to be—that the ice of the Kara Sea melts away for the most part, and that during autumn this sea is quite available for navigation.
In general our knowledge of the Kara Sea some decades back was not only incomplete, but also erroneous. It was believed that its animal life was exceedingly scanty, and that algæ were absolutely wanting; no soundings had been taken elsewhere than close to the coast; and much doubt was thrown, not without reason, on the correctness of the maps. Now all this is changed to a great extent. The coast line, bordering on the sea, is settled on the maps; the ice-conditions, currents and depth of water in different parts of the sea are ascertained, and we know that the old ideas of its poverty in animals and plants are quite erroneous.
In respect to depth the Kara Sea is distinguished by a special regularity, and by the absence of sudden changes. Along the east coast of Novaya Zemlya and Vaygats Island there runs a channel, up to 500 metres in depth, filled with cold salt-water, which forms the haunt of a fauna rich not only in individuals, but also in a large number of remarkable and rare types, as Umbellula, Elpidia, Alecto, asterids of many kinds, &c. Towards the east the sea-bottom rises gradually and then forms a plain lying 30 to 90 metres below the surface of the sea, nearly as level as the surface of the superincumbent water. The bottom of the sea in the south and west parts of it consists of clay, in the regions of Beli Ostrov of sand, farther north of gravel. Shells of crustacea and pebbles are here often surrounded by bog-ore formations, resembling the figures on page 186. These also occur over an extensive area north-east of Port Dickson in such quantity that they might be used for the manufacture of iron, if the region were less inaccessible.
Even in the shallower parts of the Kara Sea the water at the bottom is nearly as salt as in the Atlantic Ocean, and all the year round cooled to a temperature of -2° to -2°.7. The surface-water, on the contrary, is very variable in its composition, sometimes at certain places almost drinkable, and in summer often strongly heated. The remarkable circumstance takes place here that the surface water in consequence of its limited salinity freezes to ice if it be exposed to the temperature which prevails in the salt stratum of water next the bottom, and that it forms a deadly poison for many of the decapoda, worms, mussels, crustacea and asterids which crawl in myriads among the beds of clay or sand at the bottom.
At many places the loose nature of the bottom does not permit the existence of any algæ, but in the neighbourhood of Beli Ostrov, Johannesen discovered extensive banks covered with "sea-grass" (algæ), and from the east coast of Novaya Zemlya Dr. Kjellman in 1875 collected no small number of algæ[92], being thereby enabled to take exception to the old erroneous statements as to the nature of the marine flora. He has drawn up for this work a full account of the
