The prime object of the following paper is to assist in deciphering the irregular traces which represent the consonants in a phonographic record, by investigating a priori, from the causes which create the consonant, the elements which probably lie entangled in the tracing to be interpreted. Accurately speaking, the difference between vowel and consonant is not one of nature, but of function. To define either vowel or consonant, it is necessary first to define a syllable. All human speech proceeds in rapid alternations of louder and softer, more sonorous and less sonorous. These alternations vary considerably in energy; any one of them may be twice as long, or twice as loud, or twice as sudden in its rise or in its fall as its next neighbour. They seem, in fact, to tend both in duration and in form and in energy rather to a successive change than to any regularity; but each of them is a syllable. A syllable, then, is a wave of sonority, one climax of sound, with its accompanying rise and fall. Accurately speaking, this climax is a subjective one.