Sir Frederick Gore Ouseley (vide Ellis's lecture) regarded the French ton de chapelle as being about a minor third below the Diapason Normal, a' 435, and said that most of the untouched organs in the French cathedrals were at this low pitch.
This is about a semitone below the Diapason Normal, and a just minor third lower than the St Jacobi organ in the same city (1688), measured by Herr Schmahl, a' 489.2.
What was remarkable in this organ was that it had one stop which was an equal minor third lower, a' 411.4'.
Sir Frederick Gore Ouseley's comparison of the church and chamber pitches of Orlando Gibbons (vide Ellis's lecture) clearly shows the minor third in Great Britain in the first half of the 17th century.
The minor third a/c" with 88 beats per second shows scarcely any roughness, and when the beats rise to 132 per second the result is no longer unpleasant.
