A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Robin Stuart
Date: 2014 Jul 30, 14:38 -0700
Could one of the fortunate owners of an Otis King cylindrical sliderule tell me whether it has a tube locking mechanism like the German MHR1? If not: does that make it difficult to use? If so: do you know how it works?
The Otis King cylindrical slide rule appears to be very similar to the Bygrave. One difference is that the Bygrave has windows cut into the cursor tube whereas the Otis King has a solid tube with indicator marks at either end. This presumably makes for simpler construction and might be something to consider when building modern versions of the Bygrave. Because of this design, the tick marks on the two scales point outward away from the cursor tube. Drawing scales of this type is already an included feature in the code at http://fer3.com/arc/m2.aspx/Postscript-code-for-making-Bygrave-Scales-Stuart-mar-2014-g27398 . It's just a matter of setting the variable CosScaleTicksDown to true,