The river Halys formed the boundary at this time between the Median and Lydian empires: and Croesus, marching across that river into the territory of the Syrians or Assyrians of Cappadocia, took the city of Pteria, with many of its surrounding dependencies, inflicting damage and destruction upon these distant subjects of Ekbatana. Cyrus lost no time in bringing an army to their defence considerably larger than that of Croesus; trying at the same time, though unsuccessfully, to prevail on the Ionians to revolt from him. A bloody battle took place between the two armies, but with indecisive result: after which Croesus, seeing that he could not hope to accomplish more with his forces as they stood, thought it wise to return to his capital, and collect a larger army for the next campaign. Immediately on reaching Sardis he despatched envoys to Labynetus king of Babylon; to Amasis, king of Egypt; to the Lacedaemonians, and to other allies; calling upon all of them to send auxiliaries to Sardis during the course of the fifth month. In the mean time he dismissed all the foreign troops who had followed him into Cappadocia. Had these allies appeared, the war might perhaps have been prosecuted with success. And on the part of the Lacedaemonians, at least, there was no tardiness; for their ships were ready and their troops almost on board, when the unexpected news reached them that Croesus was already ruined. Cyrus had forseen and forestalled the defensive plan of his enemy. Pushing on with his army to Sardis without delay, he obliged the Lydian prince to give battle with his own unassisted subjects. The open and spacious plain before that town was highly favorable to Lydian cavalry, which at that time (Herodotus tells us) was superior to the Persian. But Cyrus, employing a strategem whereby this cavalry was rendered unavailable, placed in front of his line the baggage camels, which the Lydian horses could not endure either to smell or to behold. The horsemen of Croesus were thus obliged to dismount; nevertheless they fought bravely on foot, and were not driven into the town till after a sanguinary combat.