How does Felix nearly get shot while teaching the Portuguese troops?

While teaching the Portuguese troops, Felix nearly gets show by Wheech-Browning. Felix gives a demonstration on the use of artillery, but the round does not land where Felix had expected. In order to check the sights for accuracy, Felix decides to pace the distance to the target. Once Felix reaches the target, he hears someone fire a round. He tries to run, but an explosion knocks him to the ground. Wheech-Browning runs over in a panic and apologizes. He says he sneezed and accidentally fired the weapon.