supplement to the revolution in the mind and practice of the human race: shewing the necessity for, and the advantages of, this universal change - also a copy of the original memorial (in English, French and German) which was presented to the Sovereigns assembled in congress at Aix-la-Chapelle, in 1818, by the late Lord Castlereagh, from the author of this work, shewing the correctness of his anticipation, as proved by subsequent events, to which is added a discourse deliverd to the socialists of London on the 25th of October, 1849