8 Vignettes

Stories on the use of certain slide rules and scales, on certain sub-groupings of the Collection’s contents, and on the adventures of collecting are presented below. All stories are based on my own personal quest and only pertain to slide rules that I have collected. It is my hope that these vignettes will help introduce people to the fun of collecting and of learning about how to interpret what is found, and so are organized accordingly in the table below.

Latest Vignettes:

America’s Earliest Part II,   Gauging and Excise Tax Slide Rules,   Addition and Subtraction Logarithms,   Stadia Rules,   The Pickett Deci-Keepers,   Rhumb Line Distance and Course Computer.

Go Directly to the Appendices.

	Vignette Title	Abstract
1	A Favorite Rule	Everyone should have a slide rule that just feels right. The Faber-Castell Model 1/54, a finely-made general purpose Darmstadt rule, fits the bill.
2	Rules to the Moon	Pickett earned their place in US space history with their lightweight metal slide rules.
3	The Original 4083	Before the development of the vector slide rule 4083-3, the 1916 K&E model 4083 was an early 16-inch Duplex general purpose rule.
4	K+E Beginner’s Rules	Keuffel and Esser sold slide rules designed for beginners almost from the beginning.
5	Chicago Rules	Chicago companies played a strong role in the development of US slide rules.
6	A Boykin Discovery	Can you only find significant slide rules online? It still pays to visit your local antique stores.
7	The Long and Short of It	How the accuracy in calculations using logarithmic scales scales with scale length.
8	The Pickett Deci-Keepers	Getting the decimal point in the right location often plauges new slide rule users. Pickett came to the rescue with their Deci-Keeper scales.
9	Rules of Engravement	Slide rules were used in the layout of newspapers and magazines in the last century.
10	Out of Proportions	Determining ratios and performing proportions calculations are basic functions performed by a standard slide rule.
11	Power Rules	Log-Log scales are used for raising numbers to arbitrary powers. Their scales and use are explained.
12	Fermi’s Golden (Slide) Rule	What slide rules did Enrico Fermi use? A family member gives us insight.
13	Rule Change 4092-3	A rare transitional scale arrangement for the K&E Model 4092-3 was just sitting in the collection all along.
14	A K+E Rule of Mystery	Certain K&E slide rules with no model number remain mysterious.
15	Lt. Shaw’s 4097D	A simple search for a common model uncovers a slide rule very likely owned by a major player in the construction of the first US nuclear warships, the U.S.S. Nautilus and the U.S.S. Enterprise.
16	K+E Mystery Rules Update	The earliest date for these rules of mystery just got a little earlier.
17	The French Connection to a Mystery Rule	The scales found on a K&E Mystery rule are the American version of the French Beghin rule.
18	The Early American Favorite	Cleaning of a $10 slide rule reveals a fairly early K&E.
19	American Favorite Part II	Further study reveals new insights (to me) into the early K&E American, Favorite, and Mannheim brands.
20	Thacher’s Calculating Instrument	Thacher’s cylindrical ‘Calculating Instrument’ (patented 1881) was sold by K&E until the 1940s, yielding the accuracy of a 30-foot linear slide rule.
21	America’s Earliest Slide Rule	Palmer’s Computing Scale of 1843 is often given this title.
22	Carpenters vs. Engineers	Those folding 2-foot rules with brass slides and logarithmic scales – what are they and how do they differ?
23	America’s Earliest Part II	American-made slide rules before Palmer’s Computing Scale? Enter the Belcher Brothers – and Kutz.
24	Kolesch Rules	This New York City company sold German import slide rules, including some with special scales.
25	The Scofield Engineer’s Slide Rule	With the help of Thacher, a bridge engineer delivers an inexpensive but powerful slide rule at the turn of the 19th century.
26	Scale Wars	The K&E Duplex rule introduced in the 1890s was a major improvement to the standard Mannheim. How did other makers react?
27	Dietzgen Rosenthal Nestler Prototype	Online images of a $7 Dietzgen for sale just didn’t look right. A Nestler prototype version of Dietzgen’s update to their Rosenthal model was uncovered.
28	The Acu-Rule from Wabash	How did a Wabash, Indiana, school supply company come to sell Acu-Rule slide rules, while Lawrence Engineering was making similar items just down the road?
29	The Aver-O-Matic	Patented and produced by a young Colorado entrepreneur, this device can calculate the average of up to 10 numbers as well as compute scores of multi-problem exams, based upon the number missed.
30	Gauging Electro Rules	The electro rules were early specialty devices derived from the Mannheim design, and helped introduce log-log scales to modern slide rules.
31	An Early Home-Made Spring Calculation Slide Rule	While slide rules for designing springs became available from the major makers around 1950, Baetzmann introduced this one almost a decade earlier.
32	Spring Calcs Eternal	Besides illustrating several spring calculation slide rules of various manufacturers, the formulas used are also derived!
33	Helical Slide Rules	Accuracy is gained through helical curves on cylindrical surfaces – the Otis King and Fuller slide rules.
34	Stadia Rules	Surveyors in the field and office used special slide rules with special trigonometric scales.
35	Following the Balloons	Essentially a stadia-type calculation, slide rules were used to compute meteorological parameters through sightings of pilot balloons in flight.
36	Rhumb Line Distance and Course Computer	Find your bearing and set your course with this circular device, then compute the distance along the rhumb line before you set sail.
37	Gauging and Excise Tax Slide Rules	Ever wonder how to calculate the amount of liquid in that funny-shaped whisky barrel?
38	Slide Rules for the Sikes Hydrometer	But, how much of that liquid in the barrel is actually alcohol? And, of course, how much tax should be collected?
39	Getting to the Root	You know how to use A&D or B&C to find the square root of a number; but can you solve a quadratic equation on a slide rule?
40	Addition and Subtraction Logarithms	High precision calculations – including addition and subtraction – using logarithms and (with less precision) slide rules.
41	Vector/Hyperbolic Calculations	Imagine finding the tangent of a complex number. You really can do this. With a slide rule!
42	Hemmi 153 Scales	Now imagine finding the tangent of a complex number through the use of the Gudermannian function. Don’t worry, it’s all explained…
43	British Thornton Special Scales	Hard to get that last digit on your S/T scales when the values get close to one? The Thornton Sd/Td scales can help.
44	How Do You Byoutou?	A WWII-era Hemmi slide rule was used to train junior officers in the basics of ballistics calculations, including how to lead moving targets.

Go Directly to the Appendices.

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