"Have you ever seen a ship being chandled?"

I've never seen the word "chandled" but having watched the Inspector George Gently series I suspect that Gently was being cleverly funny because he tends to use wry humour. Also, I think the word "chandler" originally derived from "candle maker" and a ship's chandler would supply all sorts of supplies and equipment for people on ships including candles in the old times.

"He produced a florin..."

We used to have two shilling coins in pre-decimal currency Australia and older Aussies sometimes called them a florin.

"And where do you live?"
"Seventeen Kittle Witches' Grid, sir."

I'm wondering whether kittle might mean kettle, similar to the big pot used in the scene in Macbeth, "Double, double, toil and trouble..." etc. I suspect Grid might be a term for a set of streets in a grid pattern. Maybe?

"He was about middling size, and he'd got a long, straight conk."

Middling = average. Not big, not small but in the middle. A Brit reply to being asked how you are is "fair to middling", meaning good to ok/average.

[from a Scottish sea captain] "Had I kent then whit I ken noo, it'd been into the dorck wi' him.

I haven't heard or seen the past tense "kent" of "ken" (know) but it makes sense to me.