The Geographical Journal (Journal of the Royal Geographical Society): Volume IX, No. 4 [‎219r] (108/172)

THE RIVER ODER.
425
main stream, where it is first deflected from its normal west-north-west
direction by a ridge running east and west. The “middle Oder” is
itself divided into upper and lower courses at its junction with the
Obrzycko, where it enters the great Warsaw-Berlin valley. The upper
Oder proper begins at its junction with the Olsa, where the four streams
forming the original feeders unite and enter the Silesian plateau. This is
also divided into upper and lower courses at the entrance of the Neisse.
Politically, 79 per cent, of the Oder basin lies in Germany, only
0'5 per cent, outside Prussia. The sources of the main stream lie in
Austria, and of the Warthe in Russia, giving 6 per cent, of the whole
basin to the former country, and 15 per cent, to the latter.
These facts, as stated in the introduction to this report, indicate the
’ nature and extent of the area to be surveyed, and suggest the lines
followed in the inquiry itself. Space does not admit of our even naming
the thirty-five separate river-basins, each minutely described in the second
volume under the five headings, configuration, soil, water-system, culti
vation, and forest; still less can we follow the third volume through the
detailed accounts of the Oder itself and its main tributaries. This
volume is divided into three, the first section describing the bed and
the valley of each part of the Oder corresponding to the natural
divisions described above, the movements of water and ice in each,
and the “ Wasservvirthschaft,” or artificial element introduced by dams,
bridges, and the like. Section II. of this volume deals in a similar
manner with the most important tributaries, excepting the Warthe,
which, for geographical reasons already mentioned, has a whole division,
section III., to itself. Every part of the work has been executed with
the most laborious minuteness, and the facts discussed are constantly
.supported by the statistical tables, and illustrated by the innumerable
maps, plans, and sections.
The general geographical interest of the report, apart from its value
as a work of reference, centres round the papers on the climate and
geology of the Oder basin, in the first volume. The first of these, by
Prof. Dr. Kremser, discusses the interesting transitional climate of the
region from the data of air-temperature and rainfall, with a sort of
appendix on the other less widely observed elements. The variation of
temperature with height is rightly regarded as an important factor in
the temperature investigations, and special care has been taken in the
■comparison of the differences of temperature at such pairs of stations as
Eichberg and Schneekoppe (1145 and 5260 feet above sea-level), and
Eichberg and Wang (2864 feet), under varying conditions of clear and
cloudy weather, and the abnormal conditions of the FOhn wind. The
mean correction for height for the year comes out about 1° Fahr. in 330
feet, somewhat less than might have been expected, but easily accounted
for by the frequent reversal of the temperature gradient in the colder
seasons.