Frank, Francis Shalls Tull, the son of Frank S. amd Marie Tull, was born 1-9-1838 PA, and died in Houston 4-23-1917. He and his widow had TX Confederate pensions (App nos. 15356, 34231), and if you haven't already done so I'd suggest you take a look at these. You mentioned he was promoted major in the Trans-MS Dept. and from what you say it looks like he was mining nitrates for gunpowder. Do you have any documentation of this promotion?