547 pages of Instructions and notes from models of slide rules that are no longer produced. This is a reference work to preserve slide rules manuals. Many companies are no longer in business after the 1970's. The instruction manuals were never sold separately from the slide rules and many were lost over time. The project is to provide a composite hard copy book and digital of reprints of instructions from the most popular manufacturer's slide rule models. Post Instruction Books Contained in Volume 4: Book 1 – How to Operate the Mannheim Type Slide Rule, pre-WWII, 8 pages Models: 1441, 1444, 1446, 1447, 1452, etc. Book 2 – Instructions for the Binary Slide Rule, 1938 Pre-WWII, re-formatted booklet into 5 pages. Same as the Gílson Midget Binary circular slide rule. Book 3 – How to use your Post Slide Rule. 1967. 21 pages. Features Model 1447 Student Slide Rule., but references models 1441, 1444, 1446, 1447, 1452, etc. Book 4 – Self Paced Slide Rule Learning, based on 1447 student slide rule, 1967 edition, 170 pages Book 5 – Post 1450 Versatrig Duplex, 1968, 96 pages. Book 6 – Post 1460 Versalog Duplex, 1963, 130 pages. Book 7 – Post 1460 Versalog II Duplex, 1970, Added scales, 203 pages. For most users of slide rules, the Versalog II manual will provide instructions for most scales on every other slide rule, along with sample problems duplicated in the other books of this volume.