Greco-Roman practice to that of the Christian Church. The florid chants were of later introduction, and were probably the contribution of the Greek and Syrian Churches.[56] The Christian chants were, however, no mere reproductions of profane melodies. The groundwork of the chant is allied to the Greek melody; the Christian song is of a much richer melodic movement, bearing in all its forms the evidence of the exuberant spiritual life of which it is the chosen expression. The pagan melody was sung to an instrument; the Christian was unaccompanied, and was therefore free to develop a special rhythmical and melodic character unconditioned by any laws except those involved in pure vocal expression. The fact also that the Christian melodies were set to unmetrical texts, while the Greek melody was wholly confined to verse, marked the emancipation of the liturgic song from the bondage of strict prosody, and gave a wider field to melodic and rhythmic development. It would be too much to say that Gevaert has completely made out his case. The impossibility of verifying the exact primitive form of the oldest chants, and the almost complete disappearance of the Greco-Roman melodies which are supposed to be the antecedent or the suggestion of the early Christian tone formulas, make a positive demonstration in such a case out of the question. Gevaert seems to rely mainly upon the identity of modes or keys which exists between the most ancient church melodies and those most in use in the kithara song. Other explanations, more or less plausible, have been advanced, and it is not impossible that the simpler melodies may have arisen in an idealization of the natural speech accent, with a view to procuring measured and agreeable cadences. Both methods—actual adaptations of older tunes and the spontaneous enunciation of more obvious melodic formulas—may have been allied in the production of the earlier liturgic chants. The laws that have been found valid in the development of all art would make the derivation of the ecclesiastical melodies from elements existing in the environment of the early Church a logical and reasonable supposition, even in the absence of documentary evidence.