Those who would understand the phenomenon of antique tool collecting need only to look to the United States Patent System. To encourage innovative technology, the patent laws made it easy for anyone, at very little cost, to protect and document one’s innovation, even if it was of questionable utility. In this new reference book, level maven Don Rosebrook has documented, illustrated and explained the technology of more than 200 levels patented in the New England States, including many by the Stanley Rule & Level Company. If you are a serious collector of antique tools, or an antique dealer with an interest in tools, this volume belongs in your library.