ExpressionSenseRhetorical role
al-abāṭiḥPlural of abṭaḥ, gravelly low valley groundsGrammatical subject of “flowed”
al-maṭīRiding camelsThe actual moving caravan
al-aʿnāqNecksA visible cue of pace and movement
If “valley beds” is mistaken for another noun referring to the camels, the literary point disappears. The camels move, but their motion is represented so completely that even the ground seems to stream along.