where does this saying come from

[tarcinli]

does anyone know where the saying 'black as a new gate knocker' come from?

[crete]

sorry never heard of it before

[Mikeyd2]

As mentioned above....

The populous of London trembled an the mention of Newgate Prison. Once that black knocker was knocked, and they were sent in they never came out or, saw daylight again. That's how black is was, not only for themselves, but for their families. Hence the contagious fear of the very mention of the name, Newgate and, the infamous black knocker

[pie+mash]

Probably just a London saying then?
Have always used that expression "Black as Newgate's Knocker"

[lankeela]

Always used it to signify dark clouds meaning heavy rain on its way. 'Black as Newgate's knocker' over there.

Also used "bit black over Will's mother's" to mean the same thing.

No idea who 'Will' was though!