Timber!

Needing some extra good luck in your life? This is a good place to knock on wood.

You are standing in front of the fourth of five large warehouse buildings that theU.S. Army built here over a productive period from 1941-1942. After constructing the first three and a half warehouses of steel, the Army decided that steel was entirely too valuable — even for their own buildings. Hence, everything past this wall is made entirely of timber. Clearly, the change in materials was immaterial, as the buildings stand as strong as ever today.