Roller Organs are a type of organette, a hand-operated, table-top sized mechanical musical instrument, manufactured from the late 1880s through the mid 1920s by The Autophone Co. of Ithaca, New York.
See Todd Augsburger's Roller Organ Website for all the info.
Cobs are the informal name by which many collectors refer to the “rollers” which play on these instruments.
-ography, from the Greek word meaning “to write”, is the study and written record about a specified subject.
Where it all comes together:
A complete list of all known Cobs (rollers) for the Roller Organ
Specific information, such as composers and alternate titles
MIDI files enabling you to actually hear most tunes
Printed reproduction labels available directly from your own printer