Reading several books at once

There's a wonderful interview - all too short - with Joe Queenan about his reading habits.  It appeared in the New York Times recently; John Williams was the interviewer.

What endeared me to Queenan in this interview was his admission that he usually had a large number of books on the go, a manageable 24 at the moment, but up to 80 at one point.  All it requires is a good memory, he says.

I've read books in this way for years.  Over the last several months I mentioned to the young dental student I've been seeing at the Dental School that I usually have several books on the go at one time (24 might be an exaggeration for me).  He was quietly astonished: he had to finish a book before he could start another one, otherwise he'd forget what he'd been reading.  But books are worlds; you enter each one separately and they don't in any way mix themselves up - unless, of course, they happen to be all on the same subject: I've just finished one on stats and everyday life a couple of days ago and I have three others on the same topic; yes, maybe they'll blend together a bit, but that's okay.  It's a way of remembering more about the subject in hand. But books that are very different in style, tone, and subject matter don't get mixed up at all.

And the subject in hand at the moment is: what is a torch lighter?  It's a larger form of cigarette lighter, apparently, and burns at a greater heat than your usual little throwaway model of lighter.  Seems to be particularly used for cigars.   How did I get from Joe Queenan to torch lighters?   Well, via the dental student, who one day, while I was lying in the chair thinking about how many hours I'd spent there this year, he was attempting to light some sort of gas burner nearby, so as to melt some item that was going to be used in the interminable process of setting right one particular tooth in my head (it was to take an impression of some sort).  He couldn't get it to start burning, and had to get one of the dental assistants to come along and sort it out.   I think he would have been more successful with a torch lighter, by the sound of it, though it might have dealt rather too drastically to the material he was working with...!