reaching from the space immediately below the sixth added line under the bass staff to the ninth added line above the treble staff.  These two extremes, which belong respectively to the bass tuba and piccolo flute, are not at the command of every player, but they are within the capacity of the instruments, and mark the orchestra’s boundaries in respect of pitch.  The gravest note is almost as deep as any in which the ordinary human ear can detect pitch, and the acutest reaches the same extremity in the opposite direction.

[Sidenote:  The viols.]

[Sidenote:  The violin.]

With all the changes that have come over the orchestra in the course of the last two hundred years, the string quartet has remained its chief factor.  Its voice cannot grow monotonous or cloying, for, besides its innate qualities, it commands a more varied manner of expression than all the other instruments combined.  The viol, which term I shall use generically to indicate all the instruments of the quartet, is the only instrument in the band, except the harp, that can play harmony as well as melody.  Its range is the most extensive; it is more responsive to changes in manipulation; it is endowed more richly than any other instrument with varieties of timbre; it has an incomparable facility of execution, and answers more quickly and more eloquently than any of its companions to the feelings of the player.  A great advantage which the viol possesses over wind instruments is that, not being dependent on the breath of the player, there is practically no limit to its ability to sustain tones.  It is because of this long list of good qualities that it is relied on to provide the staff of life to instrumental music.  The strings as commonly used show four members of the viol family, distinguished among themselves by their size, and the quality in the changes of tone which grows out of the differences in size.  The violins (Appendix, Plate I.) are the smallest members of the family.  Historically they are the culmination of a development toward diminutiveness, for in their early days viols were larger than they are now.  When the violin of to-day entered the orchestra (in the score of Monteverde’s opera “Orfeo”) it was specifically described as a “little French violin.”  Its voice, Berlioz says, is the “true female voice of the orchestra.”  Generally the violin part of an orchestral score is two-voiced, but the two groups may be split into a great number.  In one passage in “Tristan und Isolde” Wagner divides his first and second violins into sixteen groups.  Such divisions, especially in the higher regions, are productive of entrancing effects.

[Sidenote:  Violin effects.]

[Sidenote:  Pizzicato.]

[Sidenote:  "Col legno dall’arco."]

[Sidenote:  Harmonics.]

[Sidenote:  Vibrato.]

[Sidenote:  "Con sordino."]