...n it was positively known to Rosecrans that troops from Virginia were joining Bragg, the concentration of his army was completed, excepting the reserves at Rossville and cavalry at Blue Bird's Gap of Pigeon Mountain , and at Dougherty's Gap that separates the latter from Lookout Mountain. The divisions of Wood, Van Cleve, Palmer, Reynolds, Johnson, Baird, and Brannan, about thirty thousand in number,