On the 11th of April I was present at the dress rehearsal of 'Oberon' at Covent Garden; people attended it like a regular performance; the costumes, scenery, and the stage moon introduced with the air 'Ocean, thou mighty Monster,' were admirable. This air, which was written expressly for Miss Paton by Weber while in London, made a grand effect, and so did the scena written for Braham. Both singers were allowed an opportunity of displaying their fine voices, and producing certain striking effects, which told powerfully on the audience.