"I snatched a cutlass from the pile, and some one, at the same time snatching another,"
A cutlass is so called because it was shorter than a full length sword and consequently 'cut less'. The use of cutlasses by pirates is well documented, and favoured by sailors because it was strong enough to cut through rope, canvass and even wood, but short enough to use at close range such as in onboard combat or below the decks. This rather colourful website (click here)
details many of the other kinds of weapons used by pirates.