Archive of Collections
Aristo
Blundell
Calculigraphe
Chinese
Concise
Curta
Dietzgen
Diwa
Dring and Fage
Faber
Faber Castell
Farmar
Fearns & Mear
Fowler
Gilson
Graphoplex
Gunter
Halden
Hemmi
Keuffel & Esser
Lawrence
Logarex
Lord's Calculator
Miscellaneous
Nestler
Novotni
Otis King
Pickett
Post
Russian
Sinco
Thornton
Troger
Unique
Unknown