Appearently there were a few Woodruff guns which were rifled. One example is located in the Missouri State Historical Society Museum.

I like you tend to think the guns used by the 1st Indiana Cavalry battery, which was also known as Laflar's battery of Indiana Artillery, were Ellsworth Guns, which were also called Pond's Guns, or Thyer Gun's, built on the Joslyn Gun pattern.

LaFlar's battery guns are described as being "6 pound guns on a praire carriage". This is clearly incorrect because the praire carriage can not support the weight of a 6 pound gun. However, this description tells us something about what these small steel rifled guns looked like. A Woodruff gun would have looked like an undersized, or half scale 1841 James 6 pound gun. While the Ellsworth would have looked like a almost standard 6 pound Ordaince Rifle on that praire carriage.

As a re-enactor I would think that a seasoned Civil War Era commander could have readily told the difference between the sizes of a standard 1841 James 6 pound gun and a Woodruff gun. While an Ellsworth Gun would have required a closer examination to have told the difference from the Ordaince Rifle.

So if we combine all of this together we have "a small steel rifled light artillery piece, that fire a 2 pound shot, which looked like a standard 6 pound cannon on a praire carriage".

To me this sounds like an Ellsworth gun. It was definately a weapon which the commanders were not familur with because of their failure to describe it better. I know this is rather slim reasoning, but that is what I am thinking.