Boulder Formations and Erratic Blocks. 319 



the neighbourhood of Upsala, marine post-pliocene deposites, 

 containing the Tellina Baltica, are there covered by coarse 

 gravel and large erratic blocks, as stated by Mr Lyell." 



The ingenious and ardent naturalists of Switzerland, who 

 have held that the boulder formations of Northern Europe 

 were produced by sub-aerial glaciers, never could have ad- 

 vanced so extravagant a theory had they visited that region, 

 and been even moderately acquainted with the facts above 

 stated, and others which as indisputably prove a submarine 

 origin. But there is every reason to conclude that glaciers in 

 high lands in Scandinavia, Finland, and Lapland, in very re- 

 mote times, had much to do with the origin of the erratic blocks, 

 in separating them from their parent rocks, and transporting 

 them to the coast. Sir R. Murchison informs us, that he was 

 assured by Dr "Worth, a distinguished mineralogist of St Pe- 

 tersburg, that, after a careful examination of the numerous 

 blocks scattered around that capital, there was not among 

 them a single example which could not be paralleled with its 

 parent rock in Finland. Speaking of the observations of him- 

 self and his companions, he states, that, near Jurievitz, on the 

 Volga, they found erratic blocks of a quartz rock associated 

 with others of a trap breccia peculiar to the north-western side 

 of Lake Onega, affording clear evidence that they had been 

 transported in a south-eastern direction, 500 miles from their 

 parent rocks. 



If the blocks were encased in and transported by icebergs, 

 they would be accumulated chiefly on the ridges and higher 

 parts of the sea-bottom, by which the progress of the icebergs 

 would be arrested, and where the icebergs would be fixed until 

 they gradually melted, leaving their stony cargo on the spot. 

 Such we find to be the fact. The great accumulations of the 

 blocks are not in the valleys, but on the high grounds. The 

 summits of the clifi's on the south shores of the Gulf of Finland, 

 at an elevation of 150 feet above the sea, are covered with an- 

 gular blocks of the granite, gneiss, and porphyry of Finland ; 

 they are found on the hills adjoining Lake Onega, at elevations 

 from 400 to 600 feet above the lake ; the Valdai Hills, which 

 are in some places 1000 feet above the level of the Baltic, have 

 arrested large quantities of blocks from Finland, which are 



