The information about the harmoniums at Ste Clotilde is supplied by Michael Hendron, San Francisco, California, USA. Most of it was told to him by Mr. Jean Tranchant when he showed the harmoniums in April 2012.

Mustel harmonium Modèle 39 (1861)

According to Rollin Smith (Playing the Organ Works of Cesar Franck, page 43):
“This instrument was sold September 1, 1861 and may have been purchased new for use as the orgue-de-choeur or to provide music in one of the chapels.” It was Mustel’s Modèle 39, with a rosewood case and ivory keys.
This harmonium was used for services when the Grand Orgue was not working, and Jean Langlais is said to have played it in recital. Franck, Tournemire and Langlais may have played on this instrument and composed some of their harmonium works on this instrument.
This instrument is still present in the church, but it is not in use anymore and in storage in the wedding sacristy. It will be classified and restaurated in due time.

The stop faces (left to right) are:

Pianissimo (8’ sourdine)
4 Basson 8’
Basse 8’
2 Bourdon 16’
1 Cor anglais 8’

G Grand jeu
E Expression

1 Fflûte 8’
2 Clarinette 16’
4 Musette 16’
Voix celeste 16’

Alexandre harmonium

This harmonium was made in Paris by Alexandre Père et Fils, although the identifying plaque has been removed.
It probably dates to the 1860s or ‘70s and was used to accompany services in the small chapels. The case is oak, the keys are ivory.
It is now situated behind the hight altar. One treadle is detached, but the harmonium still has a good sound, and would be a fine instrument if it were restored.

The stop list is unusual and above average (listed left to right):

S Sourdine 16’
T Tremolo
2 Bourdon 16’
O Forte
3 Clairon 4’
4 Basson 8’
1 Cor Anglais 8’

S Sourdine 8’
E Expression
T Tremolo

1 Flute 8’
4 Hautbois 8’
3 Flageolot 4’
O Forte
2 Clarinette 16’
C Voix Celeste 16’
Harpe Eolienne 8’

There are three knee levers (genouillères): Bass swell, Grand Jeu, and Treble Swell.

In January 2014, Michael Hendron recorded two pieces by Charles Tournemire on this instrument:

Mustel harmonium Modèle K |(1885)

According to Rollin Smith, around 1885 Franck had the parish buy another Mustel harmonium, a Modèle K with nineteen stops, to accompany the choir. This instrument is probably sold again in 1888, In this year a new choir organ made by Merklin was installed.

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