By Luciano Migliaccio
The work Project for a Stained-Glass Window (Cartoon of the Baptistry Window in Coventry) is a project for a stained-glass window for the Baptistry of Coventry Cathedral datable to 1958-1959. If the theme of the other drawing of the English painter is fire, in this one the artist depicts not only water as the symbol of baptism, but also the mirror, the depth, the horizontal element, and the female. At Coventry Cathedral, Piper worked side by side with Graham Sutherland, whose influence is clearly evinced in the compositional organization of the picture, though considerable less emotionally charged.
— Luciano Migliaccio, 1998