override lyric font size

[Gerard McConnell]

Hello,
Here I want to change the font size of the lyrics.  I've placed

 

    \override #' font-size = # -2

 

before \addlyrics, just after it, inside the brackets, and various other
combinations with << >>.  How do I make the lyrics smaller here?
And probably more important, is there a way I should be looking at this
problem that will allow me to figure similar ones out by myself?
(example: I can't figure out why the extra { } is required inside \score { }.)

 

\version "2.12.2"

 

\layout {
    ragged-right = ##f
}
\score {
   {
       \set Staff.instrumentName = "1"
       \clef bass
       \time 2/4
       \relative c {
                    c8 c c4  d8  d  d4  e8 e e4   c2 \bar "|."
       }

 

       \addlyrics {One and Two One and Two }
   }
}

Thanks,

Gerard