I've collected a lot of great reference books in my research of Diary of Bedlam, but by far my favorite is A Classical Dictionary of the Vulgar Tongue by Captain Francis Grose. First published in 1785, it is a collection of slang words from all corners of society.

Here are a few of the entertaining words and expressions found in this volume:

Bum fodder – toilet paper

To cast up one's accounts – to vomit

Beard splitter – A man given to "wenching"

Dog's soup – rain water

Fart catcher – a valet or footman, from his walking behind his master or mistress

Lazybones – an instrument like a pair of tongs, for old or very fat people, to take something from the ground without stooping

Mantrap – a woman's private parts

Queen Street – a man governed by his wife is said to live in Queen Street

Soul doctor – a parson

Thingumbobs – testicles

Wool gathering - Saying to an absent man, or one in reverie, as in "Your wits are gone a wool gathering."

One thing that's also interesting about the dictionary is to see how many of the words we still use whose meanings are more or less the same as they were over 200 years ago. Expressions like elbow grease, gift of gab, hodge podge, quack, ragamuffin, white lie, and ship shape all hail from this time.