stone the crows

[tallpoppies]

Why do we say stone the crows?

[Quizmonster]

Click here for the answer.

[Dkeyse]

I remember reading that down the centuries young children were employed to rid the fields of crows that were eating the crops. The nearest and cheapest thing for the youngsters to use were stones. Hence the saying!

[Grunty]

This appeared in The Times in 2003.

For many centuries, young children (and others) were employed as bird scarers, especially of crows. They used whatever means were available to frighten away the birds, hence the expression "stone the crows".
The Norfolk Labour MP, Sir George Edwards, who founded the National Union of Land Workers, even called his autobiography, written in 1922, "From Crow Scaring to Westminster", and there are many references in old country accounts to "crow scaring", "crow keeping", "crow stoning" and "rook starving". The rewards were modest - at the age of six, Edwards was paid a shilling for a seven-day week in Norfolk. In Gloucestershire, things were more varied - the going rate was from 6d a day, although if you were unfortunate enough to live in Winchcombe, all you received was 1d or 2d plus a swede.
Professor Stefan Buczacki, author, Fauna Britannica, Stratford-upon-Avon

[rojash]

But neither of the last two answers explain why we say it to express incredulity...

[MustafaTinkl]

I'd be happy with a 1d or 2d plus a Swede.

[Quizmonster]

The earliest recorded use of the phrase to suggest incredulity - which, as Rojash says, is the only current usage nowadays - dates back only as far as 1930. So, whilst the action of throwing stones at crows might be very old, saying so to express astonishment certainly is not.
As Michael Quinion - a noted etymologist and lexicographer - says on my earlier link-site, we just don't know why we say it, other than referring to its apparent origin in Australia. (The Oxford English Dictionary agrees with him, by the way.)

[Galadriel98]

Was told off by the nuns at my Catholic junior school for using the expression as it is apparently a euphemism for 'Stone me with curses'. Another one was 'cor blimey' which apparently means 'God blind me'.

Totally unlike the other answers and no idea of the accuracy of the nuns - but who's gonna argue?!

[Quizmonster]

Terrifying creatures, nuns, Galadriel, but - in matters of etymology, at least - utterly lacking the authority of The Oxford English Dictionary, I'm afraid. The 'God blind me' one is accurate, though.

[gisby]

um... My mother (English, not Australian) used the phrase when I was a lad (1950's)

The full phrase is 'Cor stone the crows', a corruption of 'Christ on the cross'. (Like Gad's 'ooks, gor blimey, etc)