...will show. We have seen how futile were the missions of Mr. Greeley to Niagara, and of Messrs. Jaques and Gillmore to Richmond, the previous summer, in the interest of peace. A few months later, Francis P. Blair, senior , a venerable politician of Maryland, who had given his support to the administration, and who was personally acquainted with the principal actors in the rebellion, then in Richmond, conceived the ide...