242 M. Kovanko’s General View of the Environs of Pekin. 
tures. Other species, as certain kinds of snakes (Gen. coluber), can 
become hydrostatically heavier than water, and lie flat and immove- 
able at the bottom, remaining on the watch in the currents of torrents 
and small rivers. in order to seize upon the fishes and other aquatic ani- 
mals on which they feed, which they afterwards carry to the bank and 
swallow. It may be presumed that in such a case, and to enable it to 
keep under water, the serpent has diminished its volume by expelling all 
superfluous air from its lungs, and retaining only what was necessary for 
the purpose of respiration.* 
A General View of the Environs of Pekin. By M. Kovanxo, 
Major in the Corps of Engineers of Mines; translated by 
Lieutenant-General Lord Grerznockx, F.R.S.E., from the 
Annuaire du Journal des Mines de Russie, année 1838. 
Published at St Petersburg, 1840. 
Pexrn is situated in a plain bounded on the north-west by 
a series of mountains belonging to branches of the chain 
Tkahi-Khanc, which takes its origin at the Yellow River, and 
is prolonged to the north-east nearly as far as the sea of the 
same name. 
The Chinese distinguish these mountains as Northern and 
Western, according to their position relatively to the capital ; 
they are, besides, equally to be distinguished by the nature of 
their rocks. 
Limestone, together with dolomite, predominate in the 
Northern Mountains, and in those of the West, diorite (green- 
stone), with all its varieties, as well as sandstone and slates 
containing beds of coal. These two series of mountains being 
cut in different directions by defiles and steep valleys, it is 
difficult to determine their point of connection. 
The Northern Mountains are a day’s journey from Pekin, 
which does not imply any considerable distance: the Chinese 
travel so slowly that they never go farther in one day than 
from 60 to 80 li,t or 34 or 44 versts. The road in the di- 
* An abridged extract from a manuscript chapter of the 6th volume of a work 
entitled Evpétologie Générale, by MM. Dumeril and Bibron, published in 
Comptes Rendus, No. 12, 20th September 1841, 
+ The li is equal to 274} sagénes of Russia. 
