Von Volbroth's introduction to world heraldry is a bit simplistic, and therefore would probably not be that satisfying to the educated layman or the heraldic artist/professional. But as an introduction, it is quite effective. Some of its suppositions and "historical" assertions have been debunked in the intervening years, but it cannot be faulted as a basic guide to terminology and praxis.
This book has one major flaw--in some of the original illustrations, the author unintentionally changed the colors of the heraldic charges. As colors are actually assigned as part of the grant of a coat of arms, and therefore part of the hieratic language of heraldry, this is a serious issue. However, footnotes correct the few instances of this. ( )