415 
Geology of the Environs of Petersburg . 
Although this is the general style of country, yet there are some 
spots of a more pleasing character, which also present the best 
situations for examining the characters of this sand. Such is the 
dell in which the Okhta runs above Mourina, especially in the 
gorge in which it is confined in passing through the hills of Copsala : 
the hills and lakes of Pargola and Souzdalskoe ; the environs of 
Toxova, and the western ascent of Riabova. In each of these 
places may be seen considerable cliffs of sand clothed with the most 
beautiful and fragrant flowers of the north in the greatest luxuriance, 
particularly Convallaria bifolia and maialis, Andromeda? calycalata 
and polyfolia, Ledum palustre, &c. Pyrolse, Orchideae, &c. 
At the western foot of Riabova, and of Coultoushy, and on the 
banks of some of the beautiful lakes of Toxova, the sand assumes a 
deep red colour, and contains a considerable portion of iron. The 
streams which issue from these hills are strongly tinged with it, and 
transport particles of it to a great distance. This may be observed 
also in some other places. 
Those outliers of this stratum which occur on the south shore of 
the Gulf, afford in general the same character as those on the north, 
just enumerated. But, in a few instances, the sand is considerably 
harder and more compact, and though it may in general be broken 
between the fingers, yet it sometimes passes into a real sandstone, 
of a fine grained sugary texture, white or yellowish. This exhibits 
some faint traces of stratification : but after frost, the laminae are 
seen separating very distinctly in all the fragments exposed to its 
influence. It is sometimes found large grained, and may almost 
be termed a conglomerate of quartzose particles, each about as large 
as a grain of rice, strongly cemented by iron. The best localities 
for examination are, the valley at Peterhof, between the Emperor’s 
English garden and the paper-mill bridge ; and a small ravine and 
Vol. V. So 
