I asked collector Joe Rainone for more images from Fred T. Singleton publications. Joe wrotes "I believe I have the entire run including #21 which, as you can see, is stamped "NOT COMPLETED but published in 1946." Inside the place where there should be images it is blank although the description of the would be images are given."
That is curious -- possibly Singleton died about that time and this was a printers dummy. Or -- it may have been published after his passing by some person without access to the images put aside for the published copy.
*See also 19th Century Peep-Show HERE