Ink

[boviner]

How do you know when you run out of invisible ink

[WendyW]

When the pen nib is no longer wet then there is no ink in your pen. One way of making invisible ink is onion juice and when you want to read it just warm the paper.

[sft42]

Uh I think it might have been a joke. Though given the standard of some of the questions recently (i mean leader of the lib dems!! where is vietnam!!) i don't know.

[DavidUK]

I will sell you some invisible ink that never ever runs out. But, it's very expensive and permanent (permanently invisible, that is).

[cupra]

Posted this a dozen times before I remembered I was using my invisible keyboard - doh!

[knowall]

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