Lot of two 1950s and early 1960s instruction books or manuals for slide rules. There is "Post Versatrig slide rule instructions" with 91 pages and copyright 1962 by the Fredrick Post Company. It has illustrations, example problems etc.. This manual is in very nice condition.
There is also "Slide Rule - How to Use It" by Calvin Bishop. Copyright 1955 with 149 pages and lot of illustrations. It has "charts and sample settings for 6 well known slide rules - keyed drills for each calculation - problems and answers in physics, chemistry, engineering, mathematics". These instructions have wear and some soil to the cover.