What are the Classic or Seminal Engineering Books in your field?

What are the classic engineering books of your field? Respond here with titles and a brief statement of why this book is a classic. I am developing a list of Classic Engineering titles from all the sources from whom I get input: Seminal Engineering Titles Worksheet - http://dld.bz/EngClassics. Also I am looking at a way to display these titles and am experimenting with a LibraryThing collection to display the results: http://dld.bz/ClassicEngineering. Any suggestions of engineering classic titles or ways to display this information are welcome.

Safety and Health for Engineers by Roger L. Brauer. It seems to be the standard for safety engineering.

Thank you Varielle!