Reading Judith Barker's excellent Agincourt: Henry V and the Battle That Made England, I came across what is, in effect, an early fifteenth-century Dilbert cartoon.  Barker, in discussing the strategic logistical planning for the Agincourt campaign, which Henry V of England undertook by invading France in the early 1400's, notes that gunpowder had been invented, and artillery had appeared on the battlefield.  Early cannons, she explains, were not only difficult to aim, being very heavy metal things with no mechanical means of orienting them, but also required considerable effort merely to fire.  The ammunition had to be loaded in the front, and a complicated, albeit primitive device, was used to get the gunpowder into the cannon.  Consequently--and this is the crucial fact--the typical artillery crew usually only managed to fire their weapon once during a battle. 

Now there is a record of a particularly efficient gunner, who, in a battle, was able to fire no less than an amazing three shots from his cannon in the course of a fight.  Witnessing this feat, his commanders concluded that he could not have accomplished it were he not in league with the devil.  So the gunner was sent off an a pilgrimage to cure his soul.