 On the death of Thomas Chalmers in 1847, Hanna was asked to write his biography, and arranged a temporary exchange so he could reside for a time in Edinburgh.The "Life of Chalmers" came out in four volumes (1849–52), to which was added a fifth, containing extracts of "Correspondence".Hanna also edited the "Posthumous Works of Dr. Chalmers", in nine volumes.