Gerald Brown was one smart dude! He put this book, "Collectible Porcelain Insulators Second Edition" together in 1972 and the information contained in it is astounding. If your interest leans toward porcelain you will discover a ton of info on a varity of manufacturers and types of insulators. 170 pages of photos, drawings, articles, patent info, etc. You have to come away a much more knowledgeable porcelain collector. $10 gets it delivered to your door. I have two copies of this book, all in very good condition.