A common feature of many older detective stories is the piece of blotting paper with part of a letter preserved on it - but in my experience ink is so quick-drying that all that blotting paper picks up is a few dots and lines. Was there ever a time when fountain pen ink really took so long to dry that a blotter would preserve much writing?

This would go more back to dip pens --- Victor Hugo's _Les Miserables_ has an instance of it --- for fountain pens, I think it's more of an anachronistic hold-over.

William

I think this is a bit like what happens on CSI and what happens in a real lab. I have just looked at the blotting paper in my notebook and on my desk, and apart from the fact that you can tell I use different inks, you would have trouble working out what I wrote, which is good as it is often my signature on cheques

Jim

Well, of course I don't remember these times, but I'd say: yeah, ink once took so long to dry. There wouldn't have been such a gereral use of blotters if it didn't.
I imagine that the longer drying time may have had two reasons - first, the flexible nibs wrote wetter than our stiff nibs today (at least mine do), second, being used to writing with fountain pens, people might have written faster than us today. So the ink wasn't yet dried when they had finished their writing. Maybe a third reason is that a short note like 'meet murderer at museum' is written fast too.

Thats all just speculation by the way, and like with sherlock holmes' deductions it may be all pure nonsense.
I've never read about such a blotting-paper-evidence, I only knew these cases in which a ballpoint written note was readable on the following page of a block. I never use ballpoint nor blotting paper, so I guess I'd be the totally waterproof criminal. Don't know what crime to commit though... /:)