Reading "Little Dorrit", I came upon this passage:
All of which Flora said with so much headlong vehemence as if she
really believed it. There is not much doubt that when she worked
herself into full mermaid condition, she did actually believe
whatever she said in it.

Flora is a good honest pleasant girl, but when she opens her mouth, she talks ninteen to the dozen until she stops to draw her next breath: I presume this is the full mermaid condition. Any ideas what full mermaid condition alludes to?

A few paras later, Dickens refers to an invalid lady as being "laid up in ordinary in her chamber". I happen to know this allusion: when wooden sailing ships were not in use, they were "parked" with their rigging and upper masts taken down -- laid up in ordinary, an expression that woulds have been familiar and comprehensible to Dickens' readers ... as, no doubt, would the memrmaid business.

Any Victoriologists out there with the answer?

Steve