(doc help, 2.19) transposition sanity check

[Graham Percival]

As a string player, I always get confused when trying to deal with the 
grammar
of transposition.  In the below excerpt from the docs, should "a fifth 
downwards"
be "a fourth upwards" ?  Or "a fourth downwards" ?  Or should the 
\transpose
be written differently?  Or...?


----
\hornNotes = { stuff in C (concert pitch, sounding pitches, whatever) }
{
 \transpose f c' \hornNotes
}
The line

\include "horn-music.ly"
substitutes the contents of horn-music.ly at this position in the file, 
so hornNotes is defined afterwards. The command \transpose f c' 
indicates that the argument, being \hornNotes, should be transposed by 
a fifth downwards. Sounding `f' is denoted by notated c', which 
corresponds with the tuning of a normal French Horn in F. The 
transposition can be seen in the following output
----