242 THE FOREST LANDS OF FINLAND. 
Vuoksi to the Gulf of Finland. This stone is used for 
laying roads, and to it is attributable the fine condition 
of the roads in Finland. There are found also in the 
same lands as the granite porphyroids other allied rocks 
syenite, diorite, &c. Porphyry, strictly so called, is met 
with in the Island of Hogland. 
‘The layer of mobile earth is composed of the débris of 
all the kinds of rocks found there, mixed with sand, clay, 
and vegetable and animal matter. Considerable areas 
are covered with sand, clay, and gravel, and require from 
the agriculturist great effort and indefatigable persever- 
ance to bring them under culture. Other grounds more 
favourable for culture are composed of clay, or of heath- 
land mixed with sand, or, what is still better, as in the 
Government of Wasa, of peat soil or vegetable earth. 
Layer upon layer of vegetable débris, decomposed and 
carbonised, are being deposited on the area of marshes, 
forming peat, which, when drained, becomes. firm arable 
land. ‘the animal kingdom has contributed more sparingly 
to the formation of the soil; but on the coast, for example 
in the Nyland, in the environs of Nadentdal, near Abo, 
in the Island of Aland, and in Central East Bothnia, the 
ground, at some places to many feet in depth, is formed of 
the débris of shells belonging to animals still living in the 
Gulfs of Finland and of Bothnia. There are found also in 
the interior of the country the remains of animals which live 
in fresh water. These are varieties of tripoli, composed of 
the scales. of infusoria, in prodigious numbers. The people 
call this tripoli Mountain Meal; and in years of dearth 
they have used it as food, mixing it with flour whereof to 
make bread.’ 
According to Dr Helms, ‘The soil of Finland is in 
the northern part, and more especially in the high- | 
lying portion of it, to some extent sandy, and in every 
respect more suitable for pasturage than for agriculture. 
A great part of the coast, however, where the level plains 
have evidently been at one time a basin of the sea, and 
