Three hours at a stretch is MUCH better than 40 minutes or so.
I am feeling more coherant, but I am trying to decide whether to get dressed and go get new glasses, or take another nap now. Both are on my agenda for today; it's just a question as to which comes first.
ETA: The new Phryne Fisher "Murder on a Midsummer Night" arrived from Australia! I have something to read while I wait for my glasses. Fortunately, I can read without them -- it's just a bit more tiring.