Nevertheless, many difficulties have been met with on account
of the weather. The autumnal rains (ISlti) gave considerable
trouble. Mackensen's army was in a very precarious situation at
the end of September, when henvy rains ruined the roads and
cut off his supplies of fuel and munitions. The rise in the
Danube, after a thaw, gave the Germans trouble in late Noveni-



248 THE JOURNAL OF OEOORAPHY [Vol. 15

ber. Bad weather, fogs, torrential rains and swollen rivers have
hampered the operations of both armies in Macedonia. The
Germans evidently made every effort to crush Rumania last
fall, before the winter checked operations, so that they might be
freer to meet the expected "spring drive" of the Allies. It was
essential that Gen. von Falkenhayn should hasten his advance
across the mountains on the Rumanian-Transylvanian border
before weather conditions became impossible. As it was, "bit-
ter cold," deep snows, rain, sleet and fog provided many hard-
ships. At the end of November, Gen. von Falkenhayn is re-
ported to have said that the length of the Rumanian campaign
would depend largely upon the weather. Continued spring-like
weather might hasten the end, whereas one sharp cold spell
might lengthen it materially.
Weather was, perhaps, one element in delaying a general
advance of the Allied troops from Saloniki. An extended win-
ter campaign by the Allies in the Balkans would have been ill-
advised.
The severe winter weather of the eastern Balkans was a
constant and important factor in the military operations there.
"Bad weather," fog, flooded rivers, impassable marshes, blinding
snowstorms, severe cold, often hampered the opposing armies
but on the whole favored the defense by delaying the German
advance, which, however, progressed with remarkable success.
