There are letters missing. In full, it would have said '...John his money...'. So an apostrophe is correct.
This has been a good thread! Nice touch from clarion about "his", which is what I was taught, too. And that early Gerry Rafferty song is a great one.
That is what I was taught at school too, but it's not in fact correct. The possessive 's' is the last vestige of English as a highly inflected language.
The Old English 'stone' would look like this:
Nom. stan (pl. stanas)
Acc. stan (pl. stanas)
Gen. stanes (pl. stana)
Dat. stane (pl. stanum)
We now just use "stone" for everything including the dative - EXCEPT the genitive which still takes an 's' ending. The varied plural endings have been eroded and we just use the nominative 'stones' for all cases.
If we're talking about a stone containing blood, i.e. the stone's blood, it's got nothing to do with "the stone his blood" as we were all taught at school, it's a leftover ending from Anglo-Saxon.
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