[78-L] SPECIAL B. Blue Amberol Cylinder??

[Clifford Bolling]

I'm recording some Blue Amberol cylinders I got from a 2nd hand store
in La Grande, OR and one of them does not have a catalog number, instead
it says 'SPECIAL B.'
 
The title is FATHER'S ECCENTRICITIES by HILL
 
What is a SPECIAL B.?
 
http://pdx78s.cdbpdx.com/CYL/SpB/tn-400_Label_BLUE-AMBEROL_SPECIAL-B.JPG
 
 
Thanks!  Cliff