If you was a little deaf-and-dumber than you are now, I'd like you better!
"Little Prudy's Sister Susy"
Sophie May
"She's a lively one if she is a dumber," said Freckles approvingly.
"Flamsted quarries"
Mary E. Waller
Th' funny part o' it is, th' dumber they air th' more they chatter.
"Bring Me His Ears"
Clarence E. Mulford