From 1913 to 1949, the chronology appears to be based on material that can be confirmed by primary documents, independent witnesses, cross-references and reasonable inference. On New Year's Day in 1912, Gurdjieff arrived in Moscow and attracted his first students, including his cousin, the Sculptor Sergey Merkurov, and the eccentric Rachmilievitch. In the same year, he married the Polish Julia Ostrowska in Saint Petersburg. In 1914, Gurdjieff advertised his ballet, The Struggle of the Magicians, and he supervised his pupils' writing of the Sketch Glimpses of Truth. In 1915, Gurdjieff accepted P. D. Ouspensky as a pupil, and in 1916, he accepted the Composer Thomas de Hartmann and his wife, Olga, as students. Then, he had about 30 pupils. Ouspensky already had a reputation as a Writer on mystical subjects and had conducted his own, ultimately disappointing, search for wisdom in the East. The Fourth Way "system" taught during this period was complex and metaphysical, partly expressed in scientific terminology.