In 1871 a great Polytechnic Exhibition was organised in this town in celebration of the two hundredth anniversary of the birth of Peter the Great. The direction of the musical section was confided to Nicholas Rubinstein, but when he resigned, because his scheme was too costly to be sanctioned by the committee, the celebrated ‘cellist, K. Davidov, was invited to take his place. He accepted, and named Laroche and Balakirev as his coadjutors. Balakirev was not immediately disposed to undertake these duties, saying that he would first like to hear the opinion of Nicholas Rubinstein as to the part which the Petersburg musicians were to take in the matter. After two months of uncertainty, the committee decided to dispense with his reply, and invited Rimsky-Korsakov to take his place. At the same time Asantchevsky (then Director of the Petersburg Conservatoire), Wurm, and Leschetitzky were added to the musical committee. This originally Muscovite committee, which ended in being made up of Petersburgers, decided among other projects to commission from Tchaikovsky a Festival Cantata, the text of which was to be specially written for the occasion by the poet Polonsky. By the end of December, or the beginning of January, the libretto was finished. When Tchaikovsky undertook to do any work within a fixed limit of time, he always tried to complete it before the date of contract expired. On this occasion he was well beforehand with the work, and sent in the cantata to the committee by the 1st of April. As he had only received the words towards the end of January, after his return from Nice, he could not have had more than two months in which to complete this lengthy and complicated score. In April he was at work again upon _The Oprichnik_, and must have finished it early in May. This, however, is a matter of conjecture, as between January 31st (February 12th) and May 4th (16th), there does not exist a single one of his letters. On May 4th (16th), 1872, the score of _The Oprichnik_ was sent to Napravnik in Petersburg. The Festival Cantata was performed on May 31st (June 12th) at the opening of the Polytechnic Exhibition, and shortly afterwards Tchaikovsky left Moscow for Kamenka, where he spent the whole of June. Here he began his Second Symphony in C minor. Early in July he went to Kiev, and from thence to Kondratiev at Nizy, accompanied by his brother Modeste. A part of this journey had to be accomplished by diligence. On the return journey the two brothers were to travel together as far as Voroshba, where Peter Ilich branched off for Shilovsky’s house at Ussovo, and Modeste went on to Kiev. Between Sumy and Voroshba was a post-house, at which the horses were generally changed.