Jim,

As an artillery fanatic and "nit-picker", an 1857 12 pdr Napoleon and a 12 pdr howitzer are two different field pieces. The howitzer has a considerably shorter barrel and the Napoleon is classified as "a gun". Confederate batteries were known for combining 2 Parrotts and 2 howitzers or 2 Napoleons (1841 6 pdrs even earlier) and 2 howitzers The two "stubby" howitzers you mention are probably 8 inch seige howitzers.

Keith