This brought back some fond memories. In my Junior year of high school (1975), I got the high score on a competitive math exam. (I even beat the seniors!) The prize was a beautiful aluminum Pickett slide rule that had a set of double-logarithmic scales in addition to the standard scales. The following year, everybody else was using TI-30 calculators, but I used that slide rule all through my senior year and even into my beginning college years. I still have it, along with its leather case and belt-strap. I actually pulled it out while I was watching this video and did the square root calculations with you. Thank you so much for this video.
Pilots still learn to use slide-rules in the form of the E6B. It's interesting because it is circular (which works well due to the way logarithms work. You can see simplified versions on some aviator watches too.
I still have my Faber Castell Rietz 111/87 which is a slide rule for machine and electronics engineering. It is really handy tool for estimating and eyeballing things. I like it.
I've got a collection of almost a dozen really old slide rules, including a 7 foot long Pickett handing on my living room wall. hah! One thing I noticed almost immediately after I started learning how to use a slide rule, was that the more you understood the slide rule, the more you didn't need to use it at all. My intuition of the "patterns" of numbers grew immensely almost overnight. We should continue to teach them in schools for this purpose!
I think we're about the same age. I got my first calculator in 1975, a Rockwell / Anita 30R "Slide Rule Memory" model which was branded House Of Fraser in the UK. But we were still taught how to use slide rules in secondary school so I bought a 6" model which was branded "WHSmith Simplified Rietz" made by Blundell, probably around 1977. Not that I can remember how to use it any more.
I was in the last cadre of high school students in Australia (circa 1975) who were taught the slide rule in Mathematics class...Faber Castell studio, I recall. Learning to fly, I used a Jeppersen Computer, circular slide rule for navigation and performance calculations. Now I have a collection of some 40 slide rules, which I use whenever opportunity arises. I joy in my "new-in-box" FC 2/83 N and its little brother 62/83 N Novo Duplex (doncha love the names of these beautiful instruments), as well as a selection of Pickets, KE, Fish, etc. Some years ago, my teacher-librarian wife arranged for me to teach classes to Primary School students in her school, for which I equipped a set of Aristo student slide rules and made up some teaching plans (on Powerpoint, forgive me!). Now I make it a point when traveling to keep in my pocket a tiny 5" Sun Hemmi which I can whip out when a calculation is needed; smart phone, nah! Paired with my favorite fountain pen, I am able to embarrass my adult children with Grandpa's mathematical sophistication. Wonderful video series, Fran.
I have my dad's slide rule and pull it out and use it occasionally. If one has to do repeat calculations or ratios, it's still much faster than a calculator. Pilots still learn to use a version of one for figuring out course vectors with wind taken into account. Yes, most use a computer or tablet, but those can fail and you'd still better be able to get where you're trying to go.
Ha ha - I used to have one of those too. Dates us, kinda, doesn't it? Every once in a while I find one in an antique or collector's shop, and then I'm tempted to buy it. Then I think ... nah. I have the DataMath calculator from TI. I think it's the first one they ever made (for the general public). Works beautifully, and has that nice bright red LED readout - which is easy to read.
I still have my K+E Deci-Lon from high school/college days! Plus the six-inch K+E "pocket" rule that has the same scales. I have a circular Pickett rule which I didn't use very much because the "folded" scales were hard to locate where the result was! I still use it occasionally just to stay "proficient" with it. Amazing devices. And, no batteries required. But, a little difficult to use when the lights go out!
Yes, I was using a slide rule at Uni in the 60's. Still have my old slide rule from back then. Also carry my old E6B when flying which is a circular slide rule for navigation and many other calcs (eg. conversions).
Big controversy back in '74 @ State Tech was calculator use. We still had those gigantic slide rules at the front of the class room that were large enough to see from the back. Some instructors that thought a calculator was like cheating for math class you lose the ability to keep track of the decimal place & so forth. Got a really a nice Post slide rule w/ leather case for $10 when dude got a new TI scientific calculator & sold his slide rule.
I got through high school with a slide rule Slide rules are all about estimating Problem now is that students cannot estimate what a reasonable result should be Thanks for showing various types of slide rules This is a gigantic deal No joke Huge, gigantic, intergalactic, or bigger
Fran, I still have my dad’s college slide rule; also a Dietzgen in a belt holster. I used it during my first year at the University of Cincinnati. The next year I was required to purchase my first calculator: a TI with the red LED’s and molded magnifying lenses. It was EXPENSIVE at the time. Now I can get a better one at Dollar Tree for 99 cents.
My modern Citizen Watch has a built in circular slide rule on the dial bezel. Probably aimed at pilots as it has "useful" constants such as IMP GAL, US GAL, STAT, NAUT, KM etc. But I remember using a slide rule all the way through Grammar School (UK High School) University and about 10 years into my engineering career - an invaluable tool. We didn't use it quite the same way as Fran, making more use of the cursor which, on my Faber Castell double sided rule, could transfer values between scales on both sides. This brute, which I have just looked out, has 12 scales on one side and 10 on the other.
When I was in the Air Force in 1985, during my training as a imagery interpreter specialist (imagery intelligence stuff), we did our photogrammetry calculations using a slide rule. In fact, we had a separate class to teach us how to do the same calculations on a pocket calculator. Their logic was, "in the field, if your calculator battery dies, you'd be out of luck if you don't know 'slip stick'." I still have mine, along with the accompanying log tables. Good times!
I bought a slide rule at a flea market because, as a kid, I thought slide rules were always a mysterious tool used by very smart people. I'm glad I bought it to study this mysterious tool and it was good to see your video and allay the fears I had about slide rules.
I really enjoyed this video . The slide rule was invented by my ancestor William Oughtred in 1622 . He was a fellow at Cambridge University and taught Christopher Wren mathematics amongst other achievements . Having said that I still don't know how to use one !
I just discovered your channels, and I'm really happy to see this video. I went to college for electronics in 1974 and part of the curriculum was a slide rule course. Those students who were Vietnam Vets were the only students allowed to have calculators, because a basic 4 function calculator cost over $100, and the Vets - with the GI Bill - were the only ones who could afford it.
Von Braun used a Nestler 23R, as did Einstein. I have one. They are scarce. The most useful would be the Pickett N4. Contrary to your claims, slide rules were used for high precision calculations. There were people called "computers" who used long 4-6 FEET long slide rules to perform calculations. Advanced slide rules can do multiplication, division, logarithms, natural logs, exponents, square roots, cube roots, tangents, sines, cosines, reciprocals, inverse functions, and more. I have a nice collection. I also used a Concise circular slide rule in high school because I could not afford those newfangled "electronic slide rules" at the time. Also, Deitzgen is pronounced "DIGHTSgen", not DEETSgen. Until a few years ago, I used a Keuffel and Esser 4181 to do quick hole size conversions for residual stress measurements (blind hole method).
I kept a short Pickett slide rule in one of my cars for calculating MPG when I filled it up. Sold that car to my father-in-law. When I realized I left the slide rule in the glove box, I asked for it back, and he wouldn't give it to me! He was happy to have a short slide rule again, and periodically gave me abuse that it was the only thing in the car that worked right.
It is just so hard to get a good sliderule these days. I still have an old half broken sliderule in my desk, because it has an amazing compound interest scale. For practical stuff I mostly switched to nomographs, because I can print those with a normal printer in case I need special conversion. While I never formally learned to use a sliderule (excluding a nonius like on the calipers) our university lab still gave out printed nomographs especially on the microwave side. Like converting from 50Ohm to 75Ohm base, or converting from resistances to reflections.
It's been many years, but a slide rule got me through electronics school on the 60s. This refresher course tells me how smart I was back then. My, how i've changed.
Dread Naught : absolutely! When I was reading Mech Eng at university in the late 60s (!), the slide rule could happily give perfectly adequate answers to long calculations by using the cursor and end flipping it as necessary. The only thing left was to locate the decimal point but that helped you use basic arithmetic. And slide rules where SO elegant ....
I inherited five slide rules from my dad. 3 of them are 9.5” basic beginner, one 10” 18 scale Keuffel &Esser K4090-3 and my favorite 5” pocket Frederick Post/Hemmi Japan 1461 Versalog with 23 scales.
When I was taking ground school for my private pilot license (1979) we had to use a slide ruler also but the functions where different. The version I used was called E6B flight computer. They still make them and lots of private pilot carry one. Think ground schools still cover there use in a 1/2 day of extra training
Three significant figures. That was the precision used in the early days of NASA's manned spaceflight program - and anywhere else. Back then the only ways to get more precision were to lease time on a mainframe computer, or to do it all by hand with pencil & paper. Then the Hewlett-Packard HP-35 appeared. I know my father got one out of curiosity, not expecting much. After less than a week of using it, he ordered more - one for each of the other engineers working with him, then later canceled his company's mainframe timeshare account. A few years later, when I started working for Radio Shack, they carried a new "pocket size" calculator in the stores. It could add, subtract, multiply and divide, AND it had a square root function. All for the low price of only $80! (That was 1975 dollars.) We kept them locked in a display case. Now of course you can get the same power for a dollar or two in practically any store. An interesting article is at www.hpe.com/us/en/insights/articles/the-early-history-of-hp-calculators-1709.html
I graduated highschool in 1973 and went on to attend engineering classes at university. We were told to buy the new Texas Instruments graphing calculator. I never figured out how to use either the slide rule(which we were also told to acquire) or the Calculator. They continue to be a mystery to me, as are logs and derivatives.. obviously I dropped out of classes.
Slide rules are still used in initial flight training to compute various aspects of flight by hand in case your electronics die. en.wikipedia.org/wiki/E6B
I still have a 12 inch that I got a few decades back. My first one was a circular rule that was a plastic business card give-away in the mid 60s. A distant acquaintance was a Shell Oil engineer who memorized the common logs from 1 to 100. That let him figure out most of slide rule functions with simple addition and subtraction on a pad of paper.
Here in former Czechoslovakia we were taught to use it in 1986. All of us had a calculator (I used the same you have on a table). But it was almost impossible to get a calculator in a shop.
"How did they get to the moon just using slide rules?" "Have you ever learned to use a slide rule? They're amazing, it's no wonder we used them to get to the moon."
Hey Fran, great vid as ever. You inspired me to dig out my old slide rule I've had since my teens, I'm now mid fifties (I don't even remember where I got this from) It is a circular slide rule by Concise, No.28N with scales (from the outer edge), D, C, C1, A & K. On the back there are ten conversion tables: Volume, Velocity, Pressure, Flow Rate, Length, Area, Weight, [Power, Energy & Heat], Temperature Conversion, and Density. Complete with instruction booklet and dark yellow vinyl pouch. Of course I had to follow along, and was happily reminded how quick and easy it is to just 'rattle off' a whole stream of values for one calculation type. Very handy. I will sort out some images and post a link soon. : )
You're after my heart again though I never mentioned the first time. I have not used a sliderule since high school and that was in 1980... Excellent video on the subject! Keep up the good work!
When you use the calculator, you think about value, but when using the logarithmic slider, you think about proportion. Best regards from Warsaw, Poland, Happy owner of a collection of 20+ sliders.
I had one in high school back in the mid '70s..used it in chemistry and physics class. I also had ( still have ) a Texas Instruments calculator, but that was never taken to school. I got my first slide rule because Spock used one on Star Trek..
Back when I got my pilot's licence, in 1990, as a pilot you still had to know how to use a particular type of circular slide rule. You can see pictures and a description here: mansfield-devine.com/speculatrix/2017/02/computing-old-school-style/
I always hated using the E6-B. Hard to see and use while in flight. I used my electronic flight calculator most of the time and kept the E6-B around just in case the batteries went dead.
I was an aerospace engineering student in college. At a college that also had a professional pilot degree program ("Aeronautical Science" degree.) The pilot students only had to have one math credit, almost universally "MTH-095" which was just "do you understand basic algebra and geometry" class. Most of them hated math. This was in the mid '90s, when even engineering students had replaced slide rules with advanced graphing calculators. I enjoyed explaining to them that they used a slide rule all the time - and one that did vector calculus. That their slide rule was far more advanced than even the old "engineering slide rule" I owned as a "relic of engineers past."
@@AnonymousFreakYT It always amazed me, how much the training materials in Ground School tried to avoid any math more complicated than integer multiplication (and it acted like even that was a lot to ask.) Seemed like a bizzare thing to do, considering how many pilots I met who had STEM degrees in everything from mechanical engineering to dental surgery.
On my first cross country, we hit some bad turbulence in our 152. Trying to work out a fuel calculation on the E6 "Wonder Wheel" while bouncing everywhere while trying to maintain some semblance of flight was exhausting to say the least. Oh, and later that evening, I learned how to clean vomit from all the nooks and crannies of of my once shiny new rotary slide rule.
@@ericmatias2799 Haven't used one of those in a very long time. I still have an E6-B but it's a full sized one. I still have that old flight calculator; an Avstar made by Jeppesen. I'm sure it was made by some Japanese company of the day but it's got Jeppesen's name in the manual. Yes, I even still have the manual. It's vintage tech from the '80s.
In my small but deliberate collection of slide rules, I have two examples with linear scales that are designed for addition! Obviously this is... rather silly, and as these rules also have relatively few scales, I can only assume they were a my-first-slide-rule sort of product.
Think i need to try one. I found my Mum's old Texas calculator (looks just like yours) when cleaning my Dad's, will have to see if i can get it working? Thank you
Not sure I agree with you on the precision aspect as the slide rule deals in whole numbers and the human needs to keep track of the decimal point. For example 1.5 x 2.5 =3.75 would be 15 x 25 = 375 with the user again keeping track of the decimal place. I am not sure about going to the moon, however can tell you that many complex airplane parts where machined by my grandfather (who taught me how to use a slide rule) in WWII to very high tolerances as there where no such things as CNC then. I also went on to use it for quite sometime to calculate quadratic equations till the arrival of the TI-55 (couldn't afford one of the HPs)...
Circular sliderules were the best. They were like infinite slide rules, because normally you would run out of scales and redo the calculation to different direction, which is annoying and confusing. Sliderules were expensive, so I used one from Nazi era, which had weird German markings and scales on the backslide.
my teachers forced as to use our brains "if you cant do it in your head you guys dont use calculatores" then i was pretty p.o ut i still can do it today in my head 35 years later
I still have a slide rule from 1960 I had as lad; Japanese made, bamboo with plastic veneer scale, the Relay No. 102 is still straight as a die. (Or should that be "as a rule"?) I also still have my Grandfather's "DRAUGHTSMAN'S SET OF CARDBOARD SCALES" EYRE & SPOTTISWOODE (PUBLISHERS). LTD., LONDON. Eight rulers A to H in Imperial in a battered cardboard sleeve, They go from Full Size to 1/10 inch to a foot. Around 1920s, if the internet is to be believed. They are in the "China Cabinet".
Fun vid Fran, thanks. I'm a retired EE, I started college with a pocket rule and had big one for homework. I saved up a year to buy a HP25C. Thanks for the memories!
I just picked up my first slide rule (not counting calipers haha) neat coincidence I have the same ti 30 calculater sitting right next to me. Just wondering if someone could tell me what that gold smaller power supply looking box/tool is in the shot on Fran's shelf.
Probably not alone in coveting scans of that reactance slipstick's intimate bits here and now in the age of colour MFP's that will print to card stock. :).
I PREDICT THAT SOME NEW BUSINESS(ES), WILL BEGIN TO RE-MANUFACTURE MODERN "SLIDE RULES",.. AND THEY WILL BECOME POPULAR, BECAUSE THEY WORL, WITHOUT BATTERIES, AND, THEY ARE ALWAYS READY TO DO THEIR WORK!!... => THEY'RE AWESOME TOOLS!!!!!!!!!
I love slide rules! My grandmother gave me my grandfather's slide rule shortly after he died. He had apparently always intended to give me one, but by the time I was ready, calculators were a thing. I proudly carried it in my backpack in college, and even found an excuse to pull it out during an exam when my calculator's battery "died". I put a note on my paper to the effect of, "Forgive slight inaccuracies - last few answers done on a slide rule." :D Great video. We'll see if the price of slide rules on eBay goes up because of this!
I always had a slide rule with me for any exam with the slightest risk of low battery. And then it became sort of superstition. And they are great for scaling. A circular version exist soley for scaling (for graphic work and layout). I know that versions existed for artillery (I've only seen a model for a mortar). And for dosis calculations (when the Bomb drops). I think I have one somewhere. As for regular slide rules I have 3, my father's (very small with physics constants and densities for Eiche, Aluminium, Messing, Kupfer, Granit and unreadable on the back), one from a flea market and one bought brand new from used building materials shop. Why? They might come in handy.
When I saw Hidden Figures I was sitting there thinking "Where the hell are the slide rules?" The engineers and the women who did computations prior to the advent of computers should have had slide rules, but there were NONE in sight.
The people known as “computers” used electro-mechanical calculators, which were bulky, noisy, power-hungry predecessors of the later pocket calculators, in order to do precise calculations. They either printed or narrow endless rolls of paper (like ATM or cash register tape) or displayed each digit by rotating a wheel to display the digit behind a window. Slide rules were used by the engineers for ballpark accuracy, and the numbers were refined by sending the inputs to the computers - or to the electronic computers when they arrived.
I still have the slide rule that I got from a very old gentleman that was a friend of my mom. I got it for mowing his lawn. I was 14 at the time (now approaching 65) and he taught me how to use it. I used it all through high school and many years later in college. I still keep it in it's original leather case. Mine is a Dietzgen Trig Log Log rule
I've just learned that a slide rule can also be used to solve factorable quadratic equations. That is, if x^2+ax+b has real roots, r1 * r2 = b, and r1 + r2 = a. Since C against D is a constant ratio, CI against D is a constant product. After setting the slide such that CI*D = b (above), visually slide along the rule until you find the combination of CI and D to satisfy the "a" coefficient. I've seen several sets of instructions for slide rules, but only one of them had this procedure. One slide to rule them all, and in the darkness bind them.
THANK YOU. After 46 years, the slide rule is simple and amazing. WHY didn't they teach this in highschool math class? I never heard about slide rule in public school and after being introduced to calculators, there was no incentive to investigate the slide rule. Even weirder, my dad was a highschool teacher and a principal.
I have 2. A simple beginner Mannheim simplex rule by K+E and my Dad’s Dietzgen polymath rule, a lot more scales. The people who figured these things out were way smarter than me.
We used slide rules for my electronics class at vocational school, but that was back in 1979 - 1981. My instructor had worked on the Gemini space program. When I went to college, I got to use an HP-33c.
I watched this when it came out and couldn’t understand it. I also was sleeping an average of 2 hours a night, I had really severe insomnia for almost 2 years. Watching it now I totally get it, it seems simple even. Little things like this make it evident how cognitively impaired not sleeping made me. I still have memory problems, fatigue, and some other random issues… sleep is precious, y’all.
I still have the slide rule I purchased back in high school in the late 60's. Only slide rules were allowed in exams at university in the early 70's. Your video takes me back in time. Also reminds me of using log tables as well as the slide rule. For complicated calculations finding the decimal place was sometimes time consuming. Dave.
I get the same from that Ti-30 as that's the beast my Aunt got for me at school. I was 16 in 1980 so it shows the change in a few years. Calculators were still banned in my school though & the start of every maths lesson would see the distribution of a pile of very tatty log books!
My slide rule is a British Thornton P271. It is a single side slide rule so may not have as many functions as other models. Back in the time when I purchased this, Thornton made a lot of products for mathematics and engineering drawing. Dave.
I still have mine from high school in the late 1960's. Used it all the way through University in the early 70's. All the hand held calculators available at that time were very expensive. The physics department had two TI45's bolted down in their common room but I used the breadbox sized calculator in the chemistry department. Now I have several hand helds including my HP41C that I used in grad school.
Gordon, i’ve still got my HP 41 CX and still love it! Got the Printer, card reader, and tape drive as well. I’ve loaded into 41CX app on my iPad and my iPhone and use them daily. Best darn calculator ever made. Although, with the TI30, you could read in bed at night with the lights out. By the way, there is an HP41.org, (I think that’s the site), that still supports them.
I worked with a security guard whose last name was Napier. I mentioned the slide rule to him. He did not know what I was talking about. I brought one in to show him what his namesake had created. He thanked me. But really, that he got to thirty years old with a name like that and never hear of a slide rule concerns me.
WOW!!!! THANK YOU, VERY MUCH, FRAN, FOR THIS INFORMATIVE VIDEO, ON SOME OF THE AMAZING CAPABILITIES, OF THES DEVICES!!! I REMEMBER WHEN MY DAD, (a "DRAFTSMAN"), FIRST GOT A TEXAS INSTRUMENTS "TI-30" HAND-HELD CALCULATOR", BACK IN THE EARLY/MID 1970'S... I WAS, AND STILL AM FASCINATED BY THE MECHANICAL "SLIDE RULES"!!!! I REMEMBER LOVING TO FIND A VARIETY OF "NOMOGRAPHS" USED FOR A VARIETY OF SPECIFIC PURPOSES, SUCH AS "MECHANICAL SPRING" PROPERTIES, WEIGHT/VOLUMES/PRESSURES,... METAL ALLOY PROPERTIES... SOIL PROPERTIES, ELECTRONICS COMPONENT PROPERTIES, MOTOR SIZES/TORQUES/VOLTS/AMPS, WIRE SIZES, ETC.... WHERE CAN WE FING "SLIDE RULES?!... i'D LIKE TO GET ONE FOR USE IN WORKING ON MODEL AVIATION" RELATED HOBBY DESIGNING...
A bit behind, working through a backlog of videos but... I saw this and lit up. I may be (relatively) young, but one thing my grandfather taught me years ago was to use a sliderule. I ended up with two of his slide rules - a Hemi 257 and a Hemi 259D. Both are really nice and have some neat features, like squares, roots, multiplication and division, etc... Sometimes, in this world of modern tech, it's just nice to use something physical. Especially when you need to consider significant digits. More decimal points doesn't always mean a more accurate calculation - your calculation should only be as good as your measurements.
I've been running through a physics textbook from 1939 with just a slide rule, then checking the math with a calculator you'd be surprised at how accurate they are especially when you account for sigfigs
