He doesn't fancy Captain Billy Morgan, thinks him rather a saphead.
The latter called their enemies "muckers," and these retorted with the term "saphead."
I bet I know what that saphead of an editor had to say without reading his letter.
She wasn't a saphead herself, but there might be some about.
A feller that kin kick like that didn't orter be called Sapwood nor Saphead nor Sapanything.