Here's an Appian reference in the summer of 36 BC naval battle of Mylae, between Agrippa and Papias.: Accordingly, the former [Pompeian crew] excelled not so much in close fighting as in the nimbleness of their movements, and they broke oar blades and rudders, cut off oar handles, or separated the enemy's ships entirely, doing them no less harm than by ramming. Those of Octavian sought to cut down with their beaks the hostile ships, which were smaller in size, or shatter them, or break through them. When they came to close quarters, being higher, they could hurl missiles down upon the enemy, and more easily throw the "ravens" [note: corvus - a plank with a spike, for grappling] and the grappling-irons. The Pompeians whenever they were overpowered in this manner leaped into the sea." and a well toned coin from 10 years earlier: Mn. Cordius Rufus, circa 46 BC. , AR Denarius, Rome mint Obv: RVFVS IIIVIR, Conjoined heads of the Dioscuri right, wearing filleted pilei surmounted by stars Rev: MN CORDI downwards (mostly off-flan), Venus Verticordia standing left, holding scales and scepter; Cupid on her shoulder Ref: Crawford 463/1b; Sear, CRI 63a; Cordia 1 Note: an excellent post here on Venus Verticordia from @Jochen1