You will find some links about FR (Family Rotary) machines in this thread -
World Rotary Restoration
The White Rotary machines from this era (possibly 1920s) use top clamp presser feet. I am pretty sure the hand wheel rotates the opposite direction from the Singer machine.
Information for loading the bobbin can be found at
Directions for loading a White rotary bobbin (White Family Rotary, etc.)
Janey - Neat people never make the exciting discoveries I do.