Permit me to doubt that! If it has a pool in it, the air is unlikely
to be very dry - in fact, it is pretty hard to get very dry air in
the UK, even in a heated building, unless you actively remove the
water vapour. If it were very dry air (semi-desert), then you would
need a belljar or similar to be able to grow any of the cool-climate,
damp-loving herbs like parsley.

Your problem is light in the winter. Most herbs will be happy in
all respects except that - even basil. Take a look at the Herb
FAQ on rec.gardens.edible, and use the following soils:

Something well-drained (soil-based or soil-less) for anything
that says it needs it.
Something water retentive (usually soil-less) for anything that
needs damp conditions.

Keep herbs like parsley well watered, but ones like thyme should
be kept dryish in low light levels. You should be able to grow
most common small herbs (e.g. not lovage), but they will not make
much growth in the winter.


Regards,
Nick Maclaren.