It's really confusing... I don't know about where you live, but here in New Zealand, they use the indirect quote for all exchange rates, so the bid price for currency is the price you buy at, so I guess it's the inverse of the direct ask price.
Even so, the book is making it confusing, it said that if there are excess limit buy orders (bids) close to the current market price then there is a tendency for higher prices, so thats what got me confused... can anyone reconcile this for me?