Found at The Book Thing in Baltimore, Maryland. Registered in Centreville, Virginia, USA.

Edit 14 Sept 2012: I read another copy of this book, and this is what I had to say:

Years have passed since the last books; now Charles Wallace is in high school and Meg is married and pregnant. When the President calls with concerns about nuclear war with the (fictional) South American country of Vespugia, Meg's mother-in-law gives Charles Wallace an ancient rune that seems to control weather, and charges him to stop the war. Charles ends up traveling through time, following the lineage of ancient Welsh settlers. This was probably my favorite of the series so far. I got a little sick of hearing the rune over and over, but all in all I enjoyed the unweaving of the legend. Recommended for fans of time travel fiction, and I don't think one needs to have read the previous books to appreciate this one.

Giving away at the Gaithersburg Book Festival.

I have read this book many times and still continue to read it, it is a very interesting book and I like it!