Glinka attached the highest value to the folk-song, of which, as already stated, he found a treasure trove ready to his hand. Nothing, though, was further from his thoughts than to employ this material in _pot-pourri_ style. Russians themselves are all agreed that it would be difficult to select one whole folk-song from any single work of Glinka's. It would naturally require a native of Russia with an accurate knowledge of these native tunes to tell us exactly when and where he used them. He seized their mood. In this way he developed every species of Sclavonic folk-song--Great Russian, Little Russian, Circassian, Polish, Finnish--with a passing flavour contributed by Persia, for undoubtedly Oriental music had, at some remote period, influenced its Sclavonic neighbour very strongly. Glinka may be said to have attained his end almost unconscious of his mode of procedure. Determined to compose Russian music, he pursued his idea unremittingly, but it was only towards the close of his life that he began to seriously analyze his effects, asking himself whence he had obtained them and in what essential points they exhibited their nationality. This inquiry involved him in a field of research bewildering in its magnitude, and one which his early death unfortunately prevented him from thoroughly investigating. Nor is the task by any means completed now, some forty years later, although many Russian musicians have thrown considerable light upon its varied aspects. The first step towards a folk-song analysis was the collecting of the melodies in sufficient numbers for comparison. So much being done, it flashed upon Glinka that there was an intimate connection between the Russian folk-song and the most ancient Russian Church music. That is to say, the melody and the freedom of rhythm typical of the folk-song had been evolved by the people, whilst its harmonization, in which lay one of its most striking essentialities, had been bequeathed it by the Church. From all that can be gathered concerning music in Muscovy prior to the introduction of Christianity, it seems justifiable to admit that harmony, or part singing, was already practised amongst the inhabitants, in what manner it is impossible to conjecture. At any rate, when the Church of Byzantium took root there, the Sclav was sufficiently advanced musically to imbibe a new idea. We know that the Byzantine Church modes were purely diatonic, so is the harmonization of the Russian folk-song in its most elementary and uncorrupted form. That the one produced the other is a most natural conclusion. In the oldest of the Russian national melodies Glinka discovered the most clearly defined type of the earliest Christian songs on record.