Corrected entry: When Palmer has shot the bad guy chasing Ducky and himself, and after he empties the clip of the Beretta (although it could be a Taurus, as they are almost identical), he continues to pull the trigger and you can hear clicks as though the hammer is being actuated. With semi-automatic weapons such as these the slide cocks the hammer from gas expansion as the shell casing is ejected from the gun. Once the clip is empty, the slide remains open (as is seen in the scene), the hammer is left in a retracted position, and the trigger is disengaged. The trigger cannot be pulled, the hammer does not move, and therefore no sound can be made. (00:39:20)
Corrected entry: Ducky states that the Romans believed that the vein of 4th finger on the left hand ran directly to the heart, thus, logically, it was the "ring" finger. However, there is no evidence that the belief originated with the Romans, nor that the 4th finger has a special vein...the fingers in the hand have a similar vein structure.
Correction: The Beretta is a double action automatic handgun and can be dry fired without the slide cycling. The trigger can cock and fire the hammer in one pull.