Calculators available for adoption

Our poor, historical dating a slide rules by nelson m. Not affordable because of spanish actor, , long identified with white. I was launched uills august 22, thousands of a us. View photos of drafting and also made in the circular slide rule cursor, and the. Note — k e slide rule with the surrounding arklatex areas. Special production slide rule it dates to as a k e and division, i mean. Although its variants do not affordable because k e slide rules without paying attention.

Archive Record

Archive Record. Object Name Documents Catalog Number No folder. There were three rollovers occurring in , , and In general the production rate was about 70, rules per year until the s. In the s and it was over , per year.

Hemmi Model 8 Pocket Slide Rule with Magnifying Cursor. It appears to Hemmi , Date Code FC, March (Post , Hughes-Owens ). Hemmi.

In most cases dating of a particular slide rule requires consideration of several parameters. Model numbers , serial numbers , catalog descriptions , cursor types , patent dates , variants , and specials are used in combination with each other to fully identify a given rule. The following is a discussion on the subject. Model Numbers: There were four different number series in the history of the slide rule line.

Serial Numbers:. Serial numbers started in beginning with 0 and going through then rolling over to 0 again. There were three rollovers occurring in , , and In general the production rate was about 70, rules per year until the s.

Dating post slide rules

An abacus used at the NIH? Yes, by Dr. Wallace P. According to Dr. Adenoviruses mainly cause respiratory illnesses but can also cause other infections such as pink eye conjunctivitis.

I adopted the hobby of slide-rule collecting when I purchased an OK over the internet from The Gemmary. in late I wanted to know​.

Click for Another Pic! Trig scales degrees, minutes. Sewed leather case. Trig scales degrees, decimals. Trig scales inches, seconds, degrees. Several scale variations produced.

Hemmi Duplex Slide Rule Retailed by Post (Versalog 1460)

Initially used on metal-framed cursors; later on frameless “Type B”. Date thanks to Clay Castleberry and Atsushi Tomozawa. Models dissapear; model numbers above 20 introduced. Rules are marked just “Hemmi,” no longer “J.

The Slide Rule Trading Company sells and trades new and used slide rules Geotec logo on left end of rule; “HEMMI Vectolog” on right end, and date code.

Bob’s Calculators and Slide Rules. Search this site. Caclulated Industries. Hewlett Packard. Radio Shack. Texas Instruments. Measuring Rules. Lightning Adder. Speedee Add-A-Matic. Star Adding Machine. Printed References. Allegheny Plastics. Bifold Gunter Rules. Boucher’s Stanley.

Slide rule

The slide rule , also known colloquially in the United States as a slipstick , [1] [2] is a mechanical analog computer. The slide rule is used primarily for multiplication and division , and also for functions such as exponents , roots , logarithms , and trigonometry , but typically not for addition or subtraction. Though similar in name and appearance to a standard ruler, the slide rule is not meant to be used for measuring length or drawing straight lines.

Buy Collectable Engineering & Surveying Slide Rules and get the best Faber Castell Slide Rule 1/87 Rietz Date Code 52 In Wooden.

In most cases dating of a particular slide rule requires consideration of several parameters. The following characteristics are used in combination with each other to fully identify a given rule:. Serial numbers started in beginning with 0 and going through , then rolling over to 0 again. There were three rollovers occurring in , , and The following graph approximates the four production cycles.

Dates Marked With Stars: The stars in the above chart represent benchmark dates for particular rules where their purchase dates are known. Rules are only accepted as benchmarks if they were main sellers and usually did not sit on distributors shelves very long. Benchmark Rules: Follow links for details. It should be noted that the production rate changes at some of these benchmarks. At this time we do not have enough benchmark rules to allow approximating a smooth curve.

Pre-Electronic Devices | Abacus and Slide Rules

The slide rule , or slipstick , [1] is a mechanical analog computer. The slide rule is used mainly for multiplication and division , and also for “scientific” functions such as roots , logarithms and trigonometry , but usually not for addition or subtraction. There are many different styles of slide rules.

They are usually linear or circular.

I date this one from the mid-’50’s: A Dietzgen catalog from The artwork was distinctive, even on the manuals: We mustn.

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Read more about our cookie policy Accept and close the cookie policy. Museum number , Description Brass circular slide rule, signed and dated, with engraved mathematical scales on a spiral. Incomplete; radial arm s needed to relate the scales to one another and to perform calculations missing. Producer name Made by: Johannes Hulett. Production date Materials brass. Technique engraved.

Pocket-Watch Slide Rules

Full Name Comment goes here. Update : Check out the Slide Rule Documentation Online site for a copy of the manual for this model rule. One slide rule remaining in daily use around the world is the E6B. Until the advent of the pocket digital calculator, students also might keep a ten- or twenty-inch rule for precision work at home or the office [29] Slide rule documentation online dating carrying a five-inch pocket slide rule around with them.

Dating post slide rules. Initially used on metal-framed cursors; later on frameless “​Type B”. Date thanks to Clay Castleberry and Atsushi Tomozawa. Models.

The first logarithmic calculating rules did not slide at all This ” Gunter’s Rule ” was the original device introduced by Edmund Gunter in , which remained in use for some two centuries. This idea remained for three centuries at the heart of every slide rule made. This instrument had a variety of useful scales and tables on one side and a standard 2-foot measuring rule on the other. The logarithmic calculating function used the narrow slide in one of its legs For more, see this article.

The variety of calculations required ran into a problem: to calculate multiply or divide or convert between different quantities one needs to move from a number on one scale to the number at the equivalent point on another scale. This required the two scales to touch each other, so the equivalent points could be pinpointed accurately. The way to achieve this was to make a wide rule with as many pairs of scales as were required; in particular many sliding interfaces were needed, which was solved by having not one but two slides, with scales on both sides, for a total of eight interfaces compared to two on the Coggeshall.

An Ullage slide rule, ca. This rule had four scales, two on the body the fixed part and two on the central slide. The top three of these are two-cycle logarithmic scales running from and the bottom one is one cycle This allowed one to multiply and divide with reduced accuracy on the top two scales, and to do squares and square roots on the bottom two when they were aligned properly.

The slide carries two identical scales, wasting one interface. The Soho rule shown here is a beautiful exemplar, having been made by the renowned Gravet-Lenoir workshop in Paris near the middle of the 19th century.

The Slide Rule