Any official documents of the 1st Indiana are difficult to come by; even the state archives have very little. Indiana was not known for preserving war records, as their Adjutant General Report attests--half the men from the 1st Indiana are "Unaccounted for," which means all records lost. I do not have much hope of ever locating useful regimental records from the regiment. The archives have on microfilm letters sent to and from members of the regiment to the governor, but nothing else. Most of the letters deal with promotions.

The OR Suppliment has their record of events indicating the 1st had the guns as early as April 1862, which may indicate they were not confiscated during a skirmish or battle but assigned to them or purchased by someone in the regiment. They are described as "four small steel-rifled guns" and nothing more. I'm heading back to the library tomorrow and hope to find more. I have a number 1st-person accounts of men who served in the 1st, but no one mentions the guns.