Primarily known for his Book of Mouth Machines, Pettrik Dilkie worked as a low-level engineer in Dorty & Dorty's manufacturing enterprises. The Book of Mouth Machines is peppered with real insights and technical detail, but its credibility is marred by Dilkie's compulsive apologetics for Dorty Dorty and her questionable commercial practices and labor standards. Read it to learn something about mouth machines, not for its revisionist historical accounts.