GEOLOGY. 245 
the tertiary period, composed of pebbles, of gravel, and of 
clay mixed with sand, which surround the interior of 
the country, mark the limits of successive masses of these 
glaciers; they are probably moraines, formed on one hand 
by gravel deposited by the glaciers, and on the other by 
the action of the waves of the sea. The most remarkable 
of these chains is that which forms the environs of the 
town of Joensuu, stretching in a curve along the south and 
south-east shores of the lakes of Karelia and Saima to 
Lahtis, at the southern extremity of the basin of the 
Paijanne, whence it turns to the south-west, and termin- 
ates near the promontory of Hango. It well merits the 
name given to it, Salpausselkd—barrier or enclosure, for 
it appears as a dyke to the lakes of the interior, the waters 
of which have not succeeded, except in two narrow passages 
—that at Imatra, and that at Keltis, on the Kymmene—to 
wear away a passage to the sea. Another similar chain, 
parallel to that mentioned, but smaller, and more frequently 
interrupted by lakes and rivers, runs a little further to the 
north by Kesaelaks, Parikkala, the islands and promontories 
of Lake Saima, Savitaipal, and thence, always holding west, 
to Anianpetol. It is thus beyond contradiction a terminal 
moraine marking the limit of the glaciers after a second 
recession, Other chains of a similar character in the 
interior of the country, the formation of which is due, 
according to all probability, to the action of the water pro- 
ceeding from the ice-sources, have a direction, for the 
most part, from the north, north-east, and the north-west, 
towards the south, south-east, and the south-west; it is in 
like manner the case that the lakes of the interior stretch 
in this direction, and that in this direction are disposed 
the stratifications of the ground.’ 
Everywhere in Finland may be seen rocks rounded, 
smoothed, and marked with striae, minute parallel scratch- 
ings. Two theories have been advanced in regard to the 
production of these elsewhere, which are no less applicable 
to the phenomena presented by the rocks in Finland, 
