how to use dual base log log slide rules by Professor Maurice L. Hartung∗ The University of Chicago Pickett The World’s Most Accurate Slide Rules Pickett, Inc. · Pickett Square · Santa Barbara, California 93102 Preface Your DUAL-BASE LOG LOG Slide Rule is a powerful modern design that has many features not found on traditional rules. These features make it easier to learn how to use the rule. They make it easier to remember the methods of solving problems as they arise in your work. They give you greater range on some scales, and greater accuracy in the solution of many problems. If you are familiar with traditional slide rules, don’t let the appearance of the DUAL-BASE rule “scare” you. You will quickly recognize the basic features of all slide rules as they have been improved in the design of this one. When you have become familiar with your DUAL-BASE rule, you will never again be satisfied to use a traditional rule. The problems of today require modern tools—better, faster, more accurate. Your DUAL-BASE rule is a modern tool. A computer who must make many difficult calculations usually has a book of tables of the elementary mathematical functions, or a slide rule, close at hand. In many cases the slide rule is a very convenient substitute for a book of tables. It is, however, much more than that, because by means of a few simple adjustments the actual calculations can be carried through and the result obtained. One has only to learn to read the scales, how to move the slide and indicator, and how to set them accurately, in order to be able to perform long and otherwise difficult ∗Any errors were almost certainly introduced by me, Mike Markowski (
[email protected]), when I typed and scanned this in from one of the manuals that came with my N4-ES slide rule.