Among the first of these offers was one from Lord Middlesex, inviting Tartini to London, and hinting that a visit to England would probably bring him in at least three thousand pounds; but it was declined in the following disinterested language: "I have a wife with the same sentiments as myself, and no children. We are perfectly contented with our position, and if we wish for anything, it is, certainly, not to possess more than we have at present." The remainder of his long and famous career passed quietly, dedicated to study, composition, and teaching. The school founded by him in 1728 soon became famous all over Europe, and sent out some of the most noted violinists. Padua was then the place of pilgrimage for all violinists, and it was not without cause that Tartini's countrymen called him "il maestro delle nazioni." This period of Tartini's labour is, above all, remarkable for his theoretic researches. Already, in 1714, he had discovered the combination tones (the so-called "third" or Tartini's tone). This discovery, a lasting and valuable acquisition to all later investigations into acoustics, led him further and further, but apart from the exact road of natural science into the nebulous regions of mystic philosophy. Tartini taught that with the problem of harmony would also be solved the mystery of creation, that divinity itself would be revealed in the mystical symbols of the tone relations. In these mystical investigations, the composer believed himself particularly favoured by the grace of God. The German composer, Naumann, who became Tartini's pupil at an early age, and who enjoyed his favour as no other did, has written down many remarkable facts concerning the master. To be initiated into the last secrets of the art of tone and the universe was Naumann's most ardent wish, but he was always put off to some future time as not yet being quite mature and worthy enough. Naumann's illustrations of Tartini's teachings resemble more a mystic and ecstatic sermon than a musical theory. Tartini died without having spoken his last word. His character in this last period of his life appears to have been amiable, mild, and benevolent. The sharp and violent disposition of his wife did not make him happy, but he nevertheless always remained considerate and tender toward her. He died in Padua, at the age of seventy-eight, on the sixteenth of February, 1770, and lies buried in the Church of St. Catherine. He perfected the art of bowing, composed eighteen concertos for five instruments, as well as several trios and a number of sonatas, and left a treatise on music. Doctor Burney translated and published, in 1779, a long letter of instructions for playing the violin which Tartini wrote from Padua, in 1760, to "My very much Esteemed Signora Maddalena." It can also be found in the life of "Ole Bull," who had a very high opinion of what Tartini must have been as a teacher.