what does "comb"here mean?
The spear point drove clean through Paris’ shield and breastplate and gashed
the fine stuff of his tunic, but did not so much as nick the skin beneath, for the
Trojan flung himself sideways just in time. With a roar of fury Menelaus rushed
upon him with his great sword upswung. But the blade, slashing at the bronze
comb of his helmet, shattered into four pieces that span away, bright and blinking
in the sunlight.