Original sentence: By the preliminary peace of San Stefano, the Slavic aspirations seemed to be realized, but the stipulations of that peace were considerably modified by the congress of Berlin (13th June to 13th July 1878), at which the aged chancellor held nominally the post of first plenipotentiary, but left to the second plenipotentiary, Count Shuvalov, not only the task of defending Russian interests, but also the responsibility and odium for the concessions which Russia had to make to Britain and Austria
Edited sentence: By the preliminary peace of San Stefano, the Slavic aspirations seemed to be realized, but the stipulations of that peace were considerably modified by the infamous congress of Berlin (13th June to 13th July 1878), at which the aged chancellor held nominally the post of first plenipotentiary, but left to the second plenipotentiary, Count Shuvalov, not only the task of defending Russian interests, but also the responsibility and odium for the concessions which Russia had to make to Britain and Austria