137
Colour and character of voices 137
Voices in combination 139
Duet 139
Trios, quartets etc. 141
Chorus 142
Range and register 142
Melody 144
A. Mixed chorus 145
Chorus in unison 145
Progression in octaves 145
Voices _divisi_; harmonic use of the mixed chorus 146
B. Men's chorus and Women's chorus 148

Editor's Preface.

Rimsky-Korsakov had long been engrossed in his treatise on
orchestration. We have in our possession a thick note book of some 200
pages in fine hand writing, dating from the years 1873-1874,
containing a monograph on the question of acoustics, a classification
of wind instruments and a detailed description of the construction and
fingering of the different kinds of flute, the oboe, clarinet and
horn.[1]

[Footnote 1: This manuscript was given to me by Alexander Glazounov;
if a Rimsky-Korsakov museum is ever founded it will be placed there.]

In his "Memoirs of my musical life" (1st edition, p. 120) the
following passage occurs: "I had planned to devote all my energies to
the compilation of a full treatise on orchestration. To this end I
made several rough copies, jotting down explanatory notes detailing
the technique of different instruments. What I intended to present to
the world on this subject, was to include _everything_. The writing of
this treatise, or, to be more exact, the sketch for it took up most of
my time in the years 1873 and 1874. After reading the works of Tyndall
and Helmholtz, I framed an introduction to my work, in which I
endeavoured to expound the laws of acoustics as applied to the
principles governing the construction of musical instruments. My
manual was to begin with a detailed list of instruments, classified in
groups and tabulated, including a description of the various systems
in use at the present day. I had not yet thought of the second part of
the book which was to be devoted to