The VIII Corps Barrier Lines
On the morning of 16 December General Middleton's VIII Corps had a formal corps reserve consisting of one armored combat command and four engineer combat battalions. In dire circumstances Middleton might count on three additional engineer combat battalions which, under First Army command, were engaged as the 1128th Engineer Group in direct support of the normal engineer operations on foot in the VIII Corps area. In exceptionally adverse circumstances, that is under conditions then so remote as to be hardly worth a thought, the VIII Corps would have a last combat residue-poorly armed and ill-trained for combat-made up of rear echelon headquarters, supply, and technical service troops, plus the increment of stragglers who might, in the course of battle, stray back from the front lines. General Middleton would be called upon to use all of these "reserves." Their total effect in the fight to delay the German forces hammering through the VIII Corps center would be extremely important but at the same time generally incalculable, nor would many of these troops enter the pages of history. 
A handful of ordnance mechanics manning a Sherman tank fresh from the repair shop are seen at a bridge. By their mere presence they check an enemy column long enough for the bridge to be demolished. The tank and its crew disappear. They have affected the course of the Ardennes battle, even though minutely, but history does not record from whence they came or whither they went. A signal officer checking his wire along a byroad encounters a German column; he wheels his jeep and races back to alert a section of tank destroyers standing at a crossroad. Both he and the gunners are and remain anonymous. Yet the tank destroyers with a few shots rob the enemy of precious minutes, even hours. A platoon of engineers appears in one terse sentence of a German commander's report. They have fought bravely, says the foe, and forced him to waste a couple of hours in deployment and maneuver. In this brief emergence from the fog of war the engineer platoon
 The author has made an exhaustive (and exhausting) effort to read all the documents, journals, and reports belonging to each of the units mentioned-no matter how cursorily-in this chapter. Of course a great number of records were destroyed; this is particularly true of the artillery battalions. The journals of most of the engineer units are extant, but these vary greatly in value. Surprisingly, many of the ordnance and antiaircraft units provided records which helped considerably in unwinding the involved tactical situation in their particular area. Any reader wishing to delve further into the story should begin with the following records: the VIII Corps G-3 Journal and Artillery AAR; First U.S. Army, G-3 Journal; the 51st Engineer Combat Battalion S-3 Operations Journal (a model of what such a record should be); the very complete 158th Engineer Combat Battalion S-3 Journal; and the brief but graphic AAR of the 58th Armored Field Artillery Battalion (whose records were destroyed).