In the base there are 6 recognizable keys
The first 4 are typical of the Martin keys.
Key 5 is typical of George Flersheim
Key 6 belong to the Victor Bonnet toys.
But of course there are exceptions.
I have searched in my photo archive or around 6,500 photos for different use of keys.
Here the exceptions that I have found (up to now) in my archive and in old Martin catalogs.
Martin used a different key that is not listed in the picture above.
Le Traîneau Russe number 40
La Conguête du Pole Nord number 217
Number 48 Le Facteur The Chemin De Fer
And then the numbers 131 till 137, (in the book Fernand Martin Toymaker in Paris on page 101) Sujets Avec Et Sans Mecanique
Flersheim has produced at least 20 own toy models of which:
-10 models have a model 5 key that we are now for sure,
-1 model have a loose key (number 229 Le Petit Patineur)
-1 a fixed key (number 246 Je Sonne La Paix)
-With 4 we now not for sure, those are soldiers with the numbers 235 – 236 – 244 and 245
4 others have Martin keys, that are:
-Number 228 La Motocycle Enrangé
-From the Le Motocycliste number 231 two keys are known, the Martin key and the George Flersheim key
-La Guerre Aérienne with number 240
-Number 243 the French Soldier is produced with a Martin key or a Flersheim key.
Number 251 La Ramier is found in three different versions, a Bonnet key, a George Flersheim key and a separate key
Madelon Casseuse D’assiettes number 260 has a Bonnet key but there are also found with a George Flersheim key.
There will probably be other pieces with different keys.
If you find a Martin with a different key, email me and preferably with a photo.