Invention by Design: How Engineers Get from Thought to Thing,

Invention, Petroski has steadfastly maintained, comes from a failure of design. The paperclip that can only be used in one direction, that becomes easily tangled in a box, or that tears the paper has led inventors to a cycle of improvements and patents. That's the story of the case studies here, many of which Petroski has used in other books--the paperclip, zipper and aluminum can appeared in The Evolution of Useful Things, the pencil in The Pencil; and the San Francisco-Oakland Bay Bridge in Engineers of Dreams. But Petroski still manages to add something new. When talking about the Bay Bridge, for example, he goes into great depth here about the impact of factors far removed from statics, dynamics and hydraulics. He looks at the importance of John Roebling's personal charisma and the impact of the 1879 failure of the Firth of Tay bridge on the subsequent construction of bridges. In the same way, his sections on ""Facsimile and Networks"" and ""Airplanes and Computers"" offer very interesting insights into the economics of implementing large-scale projects (fax machines became popular in part because of Federal Express's promotion of its new ZapMail, which turned into a $300 million bath for the company). Those who don't know Petroski's work will find this an enjoyable introduction. Those who do, will appreciate the additional gloss. (Nov.)