Well, when you get a little further, you'll find that the Solar and Telluric currents can be combined into the Lunar, so there's your ternary!

As for the "Volume 11" business, it seems that for some strange reason (likely marketing), it is part of the publisher's "Modern Day Witch" series. Given what JMG has said in the past, I very much doubt it's substance has anything to do with Wicca or witchcraft at all.