I'm confused by this one. There seem to be two separate sets of books that have the same series title. Anyone have any more information on these?
Anyway, the two pictures here are the two series. The Time-Life series is to the left; they are bound in black and have silver writing. The series to the right is from Boston Publishing Co. and it looks like they are the originals and Time-Life licensed rights to them after they were already in print for awhile. Unfortunately, though, even given this oddity, there are many titles here that I haven't been able to find any information on.