The theoretical relation between music and poetry would hardly have attracted his study had it not been that his mind was as truly philosophically and scientifically accurate, as it was poetically sensuous and imaginative. In a letter to Mr. E. C. Stedman he complained that "in all directions the poetic art was suffering from the shameful circumstance that criticism was without a scientific basis for even the most elementary of its judgments." Although the work was irksome to him, he could not go on writing at hap-hazard, trusting to his own mere taste to decide what was good, until he had settled for himself scientifically what are the laws of poetical construction. This accounts for his exposition of the laws of beauty in that unique work, "The Science of English Verse", which was based on Dante's thought, "The best conceptions cannot be save where science and genius are." The book is chiefly taken up with a discussion of rhythm and tone-color in verse; and it is well within the truth to say that it is the most complete and thorough original investigation of the formal element in poetry in existence. The rhythm he treated as the marking of definite time measurements, which could be indicated by bars in musical notation, having their regular time and their regular number of notes, with their proper accent. To this time measurement Mr. Lanier gave the pre-eminence which Coleridge and other writers have given to accent. He conceived of a line of poetry as consisting of a definite number of bars (or feet), each bar containing, in dactylic metre, three equal "eighth notes", of which the first is accented, or in iambic metre (which has the same "triple" time), of one "eighth note", and one "quarter note", with the accent on the second. Thus the accented syllable is not necessarily "longer" than the unaccented, except as the rhythm happens to make it so. This idea is very fully developed and with great wealth of curious Old English illustrations. Under the designation of "tone-color" he treats very suggestively of rhyme, alliteration, and vowel and consonant distribution, showing how the recurrence of euphonic vowels and consonants secures that rich variety of tone-color which music gives in orchestration. The work thus breaks away from the classic grammarian's tables of trochees and anapaests, and discusses the forms of poetry in the terms of music; and of both tone-color and of rhythm he would say, in the words of old King James, "the very touch-stone whereof is music." Illustrations of these technical beauties of musical rhythm, and vowel and consonant distribution, abound in Lanier's poetry. Such is the "Song of the Chattahoochee", which deserves a place beside Tennyson's "Brook". It strikes a higher key, and is scarcely less musical. Such passages are numerous in his "Sunrise on the Marshes", as in the lines beginning, "Not slower than majesty moves," or the other lines beginning, "Oh, what if a sound should be made!"