The message
from Jaques d'Alltrades contains
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The message
from Janet Galpin contains these words:
The message
from Jaques d'Alltrades contains
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While you're here, have you any idea of the name of an apple fitting
this description?

Small fruit.
Very early.
Magenta skin (all over) when ripe.
Crisp and sweet even when unripe.
Flattish, Tangerine-shape (and size) reminiscent of an overfilled
inner-tube
Deep pit at the stalk
Less deep pit at the other end
Doesn't keep well.
strong 'fruity' scent

Could it be 'Discovery'?
'Discovery' is one of the earliest (August), is deep crimson and
roundish/flattish like a tangerine/inner-tube. Mine are bigger than a
tangerine, I would say but I think size varies with conditions, age of
tree etc.
I haven't studied how deep the cavity is - and have eaten mine now, so
can't check. Apart from size, the rest fits.

ISTR having a Discovery, and IIRC, the one I'm talking about is a much,
much deeper colour, very glossy, much more scented, and a lot smaller.

I don't know how old Discovery is, but the tree these were on must have
been planted at the beginning of last century, say, 1910-1920.

Definitely not 'Discovery' then, as that dates from about 1949.
Something more unsusual by the sound of it.
Janet G