Survey of Union Pacific's switch engines and slugs as of mid-1996, just before the merger with Southern Pacific. The book details each class -- where it came from, how it is used, and dispositions. With detailed rosters. Illustrated throughout with crisp black and white photos as well as a 14 page colour section.   New. 112pp. Withers Publishing 1996. Softback.  NO-SUPS-WSLG