Quotation from: The Chessmen of Mars

Written by: Edgar Rice Burroughs

They had reached the tower now, and as they entered it from the
subterranean corridor a backward glance revealed the van of their
pursuers--hideous kaldanes mounted upon swift and powerful
rykors. As rapidly as might be the three ascended the stairways
leading to the ground level, but after them, even more rapidly,
came the minions of Luud. Ghek led the way, grasping one of
Tara's hands the more easily to guide and assist her, while Gahan
of Gathol followed a few paces in their rear, his bared sword
ready for the assault that all realized must come upon them now
before ever they reached the enclosure and the flier.