Innocent Victorians?

As Fred Goldrich pointed out on Savoynet today…

Robert Browning in “Pippa Passes”, wrote:

Then owls and bats
Cowls and twats
Monks and nuns in a cloister’s moods,
Adjourn to the oak-stump pantry.

presumably under the impression, encouraged by mischievous
friends, that a twat was a sort of hat worn by nuns.

…I don’t think I can add anything to that.