As in Ernest Borgnine's hand, which just might be calloused. The 'splanation here:
Speaking of Ernest Borgnine, although he earned an Oscar for Marty in 1955, and he was quite good in this, my all-time favorite Borgnine role is "Rogo" in The Poseidon Adventure, as in Det. Lt. Mike Rogo.
I wish I had a cool name like Rogo.