     On the morning of December 22nd, Major Don Boyer of the 7th Armored Division was leading four other Americans out from behind German lines. After participating in the desperate defense of St. Vith, his last hundred men had been cut off by the German offensive. He had ordered them to break up into five-man groups and fan out, looking for a way back to American lines. Travelling at night, avoiding roads, they had made a few miles' progress. But now their path was blocked by a main road. They would have to wait until dark to cross. Boyer's men hid behind a stone wall.
     One of the men accidently dislodged a rock; it tumbled down to the road. There were excited shouts in German from below. Then one of the Germans shouted out in English: "Surrender!"
     Boyer realized that the Germans were in just as bad a position as he was. Boyer's hillside location gave him a commanding view of all approaches, and the stone wall gave them protection against small arms fire. The Germans would need a tank or artillery to flush out his men. Maybe he could stand them off until nightfall with just a few rifles.
     "If you don't surrender immediately, I will shell you with a mortar!"
     "Damn!" thought Boyer. They would have a mortar. He reviewed his options, and the tactical possibilities. There weren't any. Boyer stood up and raised his arms.
/Mortars
     A mortar is one of the simplest of weapons: a short metal tube and a baseplate. The tube is set up almost vertically, and a mortar round is dropped down the tube. When the round hits the baseplate, the impact ignites the explosive propellant, which fires the shell up in a steep arc.
     A mortar is useful for two reasons. First, it's light. A three-inch cannon weighs 1,400 pounds; a three-inch mortar weighs 140 pounds. The cannon has greater range and accuracy than the mortar, but mortars are meant to be used by the infantry at short ranges, where accuracy is not so important. The important thing is to have the mortar there, where you need it, when you need it. Three men can carry a mortar and its shells -- a cannon needs to be hauled around by a truck. Thus, mortars are a kind of light, quick artillery.
     The other major characteristic of the mortar is its high trajectory. Most weapons shoot low-trajectory projectiles: the soldier aims just a bit higher than the target, to compensate for gravity. The bullet or shell travels in a low, flat arc. This makes aiming easier and more accurate. A mortar lobs its shell high up in a steep arc. This makes it harder to aim and requires a more highly trained operator. On the other hand, the steep arc makes it possible to drop shells over obstacles and directly into foxholes.
     Because they were cheap, light, and convenient, mortars were popular. The Americans had one mortar for every 60 riflemen; the Germans had one for every 70 riflemen./