I thought the handwriting was the same as well but then I looked it over carefully and the styles are somewhat different. Certain letters are written in two different styles between the notes.

With regards to unit information, the Chesapeake Light Artillery (4th Maryland Battery) and the Baltimore Light Artillery (2nd Maryland Battery) have details as to their service, formation, etc. in the Stewart Sifakis book "Kentucky, Maryland, Missouri, Confederate Units and The Indian Units" in his series (now reprinted by the way) Compendium of the Confederate Armies.

Still, these flags are crude and a textile analysis would tell us a lot more. I do have some doubts.

Greg Biggs