Note 209 — APPENDIX C
Reading edition
It is not easy to determine precisely the sound of χθ, φθ (χθών, φθόνος) at the beginning of words, and the Committee therefore thinks it best to leave the option of (1) sounding the first consonants as κ and π respectively, and the θ as it is in other positions (this applies both to students who adopt the fricative and to those who adopt the primitive aspirate pronunciation of the letters in other positions), or (2) where the fricative pronunciation is adopted, of sounding χ and φ, in this position also, respectively as Scotch ch and English f.