usion of a
musical composition, if left devoid of cadences in sufficient number
and force, may be gleaned from an experimental test of the effect of a
page of prose, read with persistent disregard of its commas, colons,
and other marks of "cadence."

* * * * * *

Another evidence of Form in music, that is at once subtle and powerful,
rests upon what might be termed the _linear_ quality of melody. The
famous old definition of a line as a "succession of points," tallies so
accurately with that of melody (as a "succession of single tones"),
that it is not only proper, but peculiarly forceful, to speak of
melodies as _tone-lines_. Our conception of a melody or tune, our
ability to recognize and reproduce it, depends far more upon its
undulations, its rising, falling, or resting level, than upon its
rhythmic features (the varying lengths of its tones). These movements
trace a resonant line before our mind's eye as surely, though perhaps
not as distinctly, as the pencil of the artist traces the lines of an
image upon the paper; and this process is going on constantly, from
beginning to end, in every piece of music. In a portrait it describes
the contours of face and figure,--in a word, the _Form_; in the musical
composition it fulfils, to a great extent, the self-same mission, that
of defining the Form. One clear, predominating tone-line traces the
"air" or tune of the piece; and this is often the only line that
arrests the hearer's attention; but there are other tone-lines, less
prominent and less extended and coherent, gliding along harmoniously
beside the Melody proper, which (something like the shading in a
picture) contribute to the richness of the design, and perform their
share in proving and illuminating the Form of the whole.

This is most salient in music for orchestra, where each player
describes an individual tone-line, rendered all the more distinct and
recognizable by the specific "color" of his instrument; and that is the
chief, perhaps the sole, reason why the orchestra is esteemed the most
complete and perfect medium of musical expression.

UNITY AND VARIETY.--As much as opinions and beliefs may differ, among
music critics, as to the necessity of Form in music, and the conditions
of its existence, no reasonable objection can be taken to the
hypothesis that _Clearness and Attractiveness_ are the two vital
requisites upon which the enjoyment of any art depends. The art