Calculators available for adoption
This object record is currently incomplete. Other information may exist in a non-digital form. The Museum continues to update and add new research to collection records. Copyright for the above image is held by MAAS and may be subject to third-party copyright restrictions. This includes artworks, artifacts, images and recordings of people who may have passed away, and other objects which may be culturally sensitive. Next Continue. Over the 19th and much of the 20th centuries the slide rule was the primary instrument for calculation used by many people engaged in the trades and in engineering. Although originally invented in the 17th century, and widely used for gauging or estimating the quantities of certain products such as alcoholic spirits it took until around for the slide rule to become generally popular with those for whom mathematics was a daily task.
Vintage Slide Rules
Post sold a wide variety of slide rules, both under its own name and under the names of various manufacturers. Post itself actually made no slide rules; even those rules that bore the Post brand name were manufactured by others. Until about , Post slide rules were made by a variety of German manufacturers.
Teledyne Post ceased selling slide rules in the mid s. POST Dating Post Brand Slide Rules. * Before , Post brand slide rules were made by various.
This part of the Hemmi Catalogue Raisonne lists Hemmi-made slide rules for which I know no model number. These rules were given names “Calorie,” Real Estate” instead of model numbers, or were made for other companies SKF, Carrier, Foxboro or made for the military. There are also some rules which probably were assigned Hemmi model numbers but I don’t know what that model number was–e. I will be greatly indebted to anyone who can supply any more information about any Hemmi slide rule.
Ltd was still in business in Tokyo. They are engaged in development and manufacturing of printed circuit boards, fluid control devices, semiconductor manufacturing equipment and several minor businesses–one of which is the design and manufacture of custom slide rules of the style I would call a “slide chart. See last item on this page for a photograph.
Descriptions here are arranged by type of construction. Only name or function is known. Paul Ross. Designed and distributed by SKF. Implements various calculations related to bearings.
Sliding Through Science History, Part 2
Post Versalog II slide rule. Date: Inventory Number: Classification: Slide Rule. Maker: Hemmi Maker: Frederick Post Company circa
My collection of Sun Hemmi slide rules. Their Versalog model, made exclusively for Post (model ) and Hughes Owens ( or Also around this time, they started engraving 2-letter date codes on all their rules.
Although the date codes were prominently engraved and paint-filled in the early years, from the late ‘s onward they can be hard to spot as they are only lightly engraved in small letters, often near an edge. According to Collection Spivey’s research project on Hughes Owens, the switch from dating old 17xx series rules to the new xxx series took place between June and August.
Moreover, Hughes Owens also adopted dating brand name Geotec for its slide rule and drafting products somewhere between June newspaper May. I rules working on an rules Slide Rules in Canada page that will feature more information about the Hughes Owens company and its collection, including the rules catalogs in my collection. Please stay tuned! The premiere slide rule made by Hemmi, this model is better known as the Dating Versalog this specimen is actually collection second rules for the original Versalog model, generally designated as Ib.
John & Della Ireton
Guide – Hemmi Date Codes. Greg’s Slide Rules. After Hemmi dropped the ‘Made in Occupied Japan” logo in about they began placing date codes on certain rules. This code took the form of a two letter code marked somewhere on either the top or bottom of the rule. This code gives the year and month of manufacture and allows the rule to be dated fairly accurately.
Depending upon the age of the rule the code may be in a different location.
“Dad says that anyone who can’t use a slide rule is a cultural illiterate and would care mainly about its usability, not its date of manufacture.
Over the past twenty years I have given much thought to analog clocks, sorobans, and slide rules. The case of the analog clock is the simplest: for a time, it looked as though analog clocks and watches might be replaced completely by digital clocks and watches. That did not happen. Because I have surmised, and undoubtedly there is considerable research that backs me up people cannot organize their time using a digital clock the way that they can with an analog.
Twenty minutes on an analog clock is one-third of a pie. I’ve thought less, but some, about sorobans. The word is that these analog calculators are still in use in Japan, where most people can add and subtract numbers more quickly with sorobans than they can with digital calculators. Apparently, a calculator is faster for multiplication and division.
Otis King’s Patent Calculator
Skip navigation! Story from Living. In , the DM slide is a classic move. Ordinarily, it happens between two people who follow each other, so you should be relatively protected from total strangers. Except, of course, for any brave souls who leave their DMs open, meaning the approach could come from literally anyone.
If you have a K&E rule with a serial number that you know its purchase date, it would necessarily be in the fourth series of serial numbers produced after .
Sokoloff’s work opened up the field of neuroscience by providing a way to image how brain function affects mental health. The power came from the number of scales and the use of lettering, which enabled the log-log scales to be doubled. Pickett dropped the Eckel name in , and the logo dates from , but scientists would care mainly about its usability, not its date of manufacture. This powerful tool belonged to Dr. Joseph E. Are you beginning to think that slide rules look alike? There are specialized scales for cubes, spheres, voltage, etc.
Because slide rules are based on the relation of numbers to each other, and not just counting, they are good for teaching higher mathematical understanding. This pocket-sized Dietzgen below was owned by Dr.
Carrier Ductuler (Bamboo), 1961.
My first serious rule was a Hughes-Owens Versalog model. Wonderful instrument! Went to the army for two years, and when I returned there wasn’t a slide rule in sight. My HP saw me through my degree and my first years in the aerospace industry. Anyway, when I became aware of the date codes, I wondered why I couldn’t find mine. Now I know.
Circular Rules: The original type of slide rule, a bit harder to find, but also It’s inches long, and has the same scales as the Post, but with the There is no date on the package or the instructions, nor a copyright on the.
Low cost two color simplex rule. Plastic body rule with unusual blue tinted slide and two color scales. Basic student rule with trig scales, the T, ST and S scales have complimentary angles marked in red, and the scales are all self-documenting on the right hand side. Reversible slide has 3 log log scales. Unbreakable plastic cursor.
About June, The last Post Versalog II is made.