The Great Organ Cavaillé-Coll

Choir organ

Until 1888, there was no choir pipe-organ at Ste. Clotilde due to placement difficulties (1,2). However, in 1861, a Mustel harmonium was bought to serve as choir organ (3).
The new electro-pneumatic system of Schmœle & Mols used by Merklin offered the posibility to install an organ using opposite sides of the choir. In a letter to Merklin, Cesar Franck wrote in 1887 (see picture of tghe letter below): ... nous allons donc enfin le posséder cet orgue si désiré et attendu depuis si longtemps, grâce à votre système électro-pmeumatique, que je trouve simplement merveilleux.
Thus, a choir organ was ordered and made by Merklin, inaugurated on February 20, 1888 (14 stops). A novelty in Paris! The organists who examined and approved the instrument included Franck, Dubois, Samuel Rousseau and Verschneider. The committee reported: An organ of electro-pneumatic design has just been installed in one of the leading churches in Paris. This is a historic event in organ building, because of the resources afforded by the system which the builders employed. It would be a mistake to expect Ste Clotilde being a replica of the design essayed about twenty years ago by the late Barker. (4)
The console was situated among the choir pews, at some distance from the pipes, which were placed on either side of the chancel; the wind supply was hidden behind the altar.
This organ has disappeared. It is unknown why it has been removed and when.

The present choir organ was built around 1935-36 by the Cavaillé-Coll-Pleyel company. The organ consists of only a swell case. It is placed on the first floor of the gallery on the left side. It has 12 stops (10 real), 2 keyboards and a mechanical transmission. In 1965, works were performed by J. Picaud (transfers of the Doublette of the Récit to the GO et the Nasard of the GO to the Récit and (on request of François Tricot) transformation of the Basson-Hautbois of the Récit to a Trompette 8).
The organ has not been and will not be restaurated and is not in use anymore.

Composition of the choir organ

Grand-Orgue (61 notes) Récit (61 notes) Pédale (32 notes)
Bourdon 16
Flute harmonique 8
Flute octaviante 4
Doublette 2
Cor de nuit 8
Gambe 8
Voix céleste 8
Flute douce 4
Nasard 2 2/3
Trompette 8
Soubasse 16 (~ Bourdon 16 of the GO)
Bourdon 8 (~ Cor de nuit 8 of the Récit)
Accouplements d'octaves graves: GO - 8, GO - 16
II/I
Pedal-I/Pedal-II
Swell (whole organ)

(1) According to Fenner Douglas (1980, p. 1410, 1999, p 151) Cavaillé-Coll placed - in attendance of the great organ - a temporary choir organ of four stops in 1857, replaced in 1858 by an instrument of 14 stops on the provisional organ tribune.
(2) According to Ann Labounsky (based on a personal letter to her by Pierre Cogen) there was originally a harmonium with pedals on the choir loft; the bass line was supplied by a string double bass.
(3) According to Rollin Smith (Playing the Organ Works of Cesar Franck, page 43)
(4) The older system of Barker was used in e.g. St Augustin

Sources:
Fennar Douglass Cavaillé-Coll and the musicians Raleigh 1980
Fenner Douglas Cavaillé-Coll and the French Romantic Tradition. Yale University Press New Haven and London, 1999.
Ann Labounsky Jean Langlais The man and his music Amadeus Press, Portland, Oregon, 2000. ISBN 1-57467-054-9
Carolyn Shuster Fournier Les instruments à claviers d'accompagnement de la basilique Sainte-Clotilde La tradition musicale de la basilique Sainte-Clotilde de Paris L’Orgue n° 278-279 (2007/II-III) 159-161 ISSN 0030-5170
Orgues de L'Ile de France Tome 5 Klinksieck, Paris, 1992 ISBN 2-252-02848-3, 2-252-02941-2 2-252-03121-2

Orpha Ochse Organists and Organ playing in nineteenth-century France and Belgium (;age 100) Indiana University Press Bloomington & Indianapolis 2000.
Rollin Smith Playing the Organ Works of Cesar Franck Stuyvesant, N.Y.: Pendragon Press, 1997