A rather thick book full of sketches, writing, and rather lengthy explanations.
The Compiled, Coallated, and Mostly Completed Works of Falnirin Artemetio Grabhock Narleknocker Maidusimum Grantin Galdelal the Fourth, Apprentice Engineer, Chapter 5 Subchapter 3 of the Local Engineers Society for the Improvement of the Gnomish Communities of Gilderock, Volume 1.