THE EEGION OF LAKES. 327 



of Finland, to which it drains through the ITeva. This stream, only 36 

 miles long, ranks in volume with the great rivers of Europe, discharging from 

 103,000 to 104,000 cubic feet per second — a discharge greater than that of the 

 Rhine or Rhône, and surpassed outside of Russia by the Danube alone in Europe, 

 and sufficient to have already changed into a fresh-water basin the eastern section 

 of the Gulf of Finland beyond Kronstadt. It varies in width from 850 to 4,200 

 feet, and the steamers plying on it generally find 7 to 10 feet on the reefs. 

 Still, like the other rivers flowing to the gulf, it forms porogi, or rapids, some of 

 which are impassable to all except flat-bottomed craft. Between the quays of 

 St. Petersburg it has a depth of from 20 to 50 feet, but beyond the delta its 

 various branches — Great and Little Neva, Great, Middle, and Little Nevka — are 

 separated from the sea by bars and sand-banks inaccessible to vessels drawing more 

 than 7 feet. On the other hand, very little sedimentary matter is carried down, so 

 that the channels are liable to but slight change, and the delta was increased by 

 1,570 acres only between 1718 and 1834, or at the yearly rate of about 14 acres, 

 and of 6 or 7 feet along its whole front. The alluvial soil is only 79 feet thick, 

 as shown by the borings of an artesian well sunk 660 feet to a body of water 

 flowing under the strata of Finland granite supporting the alluvia. 



Thanks to Ladoga, which regulates the discharge, the difference between high 

 and low water is inconsiderable, and the floods would be in no way dangerous 

 but for the west winds blowing right up the stream, and capable of inundating 

 St. Petersburg if they lasted several days. During the floods of November 7th, 

 1824, the water rose more than 12 feet above the sea-level, deluging the greater 

 part of the capital, and it rose again to nearly the same height in 1879, though 

 it seldom exceeds 12 inches above the gulf. Another danger arises from the 

 breaking up of the ice in Lake Ladoga, which sends down huge masses, often 

 causing great havoc along the banks, and destroying the quays of St. Petersburg. 

 Observations extending over one hundred and fifty years show that the Neva is 

 ice-bound on an average for 138 days yearly, but with great fluctuations, varying 

 from 87 days in 1822 to 194 in 1852. 



Climate. 



The climate of the Neva basin, lying under the sixtieth parallel of latitude, is 

 naturally unfavourable to any except the hardiest plants, capable of resisting the 

 long winter frosts and the thaws of spring. The oak, which reaches the latitude 

 of Gefle in Sweden, does not grow spontaneously in the Ingrian forests, flourish- 

 ing only on the banks of the Msta, east of Lake Ilmen. The poplar, elm, maple, 

 and ash, so characteristic of the forests in the temperate regions of Central 

 Europe, are here found only in well-tended private grounds. Even the silver 

 pine is rare, nothing growing freely except the birch, alder, aspen, willow, and 

 service-tree. The northern limit of wheat is also marked by a line drawn through 

 Ladoga, and to the south of Onega. 



Under such unfavourable conditions this region could scarcely become very 

 thickly peopled, and one of the most remarkable phenomena of contemporary 



