Anabasis

On the following day, after Seuthes had burned up the villages completely and left not a single house, in order that he might inspire the rest of his enemies also with fear of the sort of fate they would suffer if they did not yield him obedience, he went back again.

Then he dispatched Heracleides to Perinthus to sell the booty, so that he might get money to pay the soldiers with; while he himself and the Greeks encamped on the plain of the Thynians, the inhabitants abandoning their homes and fleeing to the mountains.

There was deep snow on the plain, and it was so cold that the water which they carried in for dinner and the wine in the jars would freeze, and many of the Greeks had their noses and ears frost-bitten.

Then it became clear why the Thracians wear fox-skin caps on their heads and over their ears, and tunics not merely about their chests, but also round their thighs, and why, when on horseback, they wear long cloaks reaching to their feet instead of mantles.