Don't miss this unusual find! Slide the cursor until the number on the D scale which is against 1 on the C cursor is the same as the number on the B cursor which is against the base number on the A scale. Basic Multiplication The most basic procedure carried out on a slide rule is the multiplication of two numbers u and v using the C and D scales. Don't miss your chance to get a brand new rule! You can enter and read a number typically to two or three decimal digits only. Duke it out over the net. Used Includes Slide Rule, Instructions, Leather Case. They had a master, and the guy would just sit there and cut the grooves and hand-engrave the numbers in. Sh is the inverse of the hyperbolic sine.
Very advanced duplex rule with hyperbolic scales. In the heyday of slide rules that was considered a trivial task that you did in your head, or on a piece of paper if you had to. So before you use your slide rule as suggested in the tables you'll have to think carefully about what you are doing, which never hurts anyway. What Can You Do With A Slide Rule? Breitling, a Swiss watch company, released their pilot's slide rule and their pilot's wristwatch in 1952. Since there is nothing to stop people from other countries buying at these prices, with the addition of extra freight charges, then the prices can be considered valid globally.
Archived from on 14 February 2009. The sliding center bar is sandwiched by the outer bars which are fixed with respect to each other. This allowed the user to directly perform calculations involving roots and exponents. He made the slide rules in his home and shipped them out to folks. Pocket rules are typically 5 inches. From then on, all that was left to do is introduce better materials, notably plastic, and add more and revised scales, which could number upward of 30 on the largest duplex rules.
The onefold cursor version operates more like the standard slide rule through the appropriate alignment of the scales. So there were several models sold that had a math calculator on one side and a slide rule glued to the back to do those other functions. I have just learned of a old local retailer, now gone, was producing a range of slide rules. If there is history of its use by yourself or a family member, please include a short biography and a photo of the original owner or yourself. The most popular are , usually and , log 10 for taking the log of a value on a multiplier scale , ln and e x scales. I am not trying to sell it as an antique. Proportion wheels are still used in graphic design.
More elaborate slide rules allow other calculations, such as , , logarithms, and. The Fuller rule used a much larger cylinder with spiral scale 42 feet long. 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. See Resources below for a paper on the multiple complex steps which this company used to make high precision slide rules. This would change in the 19th century. They also had these really large teaching and demonstration slide rules. This is an example of a 'self indicating' rule because the function of each scale is given on the right; not all rules featured this.
The variables have to be in certain ranges, and you may have to be judicious about which variant of the relevant scale you use to read your result. Stupid me stoopud stoopud stoopud. I vividly recall that at the end of 1974, the students who were still using slide rules were given an additional 15 minutes on the final examination to compensate for the computational advantage afforded by the calculator, hardly adequate compensation in the opinions of the remaining slide rule practitioners. See how slide rules survive today in the form of slide charts still made in the millions annually. Slide rules were put on every airplane to calculate mileage for navigation. New condition box has a missing flap and a small spot where the green surface was torn off, apparently when a price sticker was removed.
Thank you for your support and consideration. The Dietzgen manuals have a few pages at the end with a large number of conversion factors. . In general, if is the function corresponding to scale 1 again, as listed in Table 1 , the function corresponding to scale 2, and the function corresponding to scale 3, then the result that you read on scale 3 is where the base of the logarithm is the length of the slide rule and exp is the inverse function of log. Examples of early 70s models Four typical models spanning a basic to a most advanced example available in the 70s are presented below. The RotaRule featured a friction brake for the cursor.
I wanted it so I could quickly calculate the price per ounce for comparison shopping. Click on picture to enlarge. The rule is about 13. At the time, a choice of slide rules were still commonly sold in any high street stationers such as W H Smiths and Boots the Chemist the latter who had their own branded range. Two Variables Of course the number of possibilities is vastly increased by allowing the slide to move.
For example, to calculate 3×2, the 1 on the top scale is moved to the 2 on the bottom scale. As the curator of the International Slide Rule Museum sliderulemuseum. C is on the slide, and D is on the body. People would write their names in case it got lost. I suppose the rationale for not including the manual was that the pocket rule was adjunct to the 10-inch model, which did come with a manual. Some rarer specialist rules can command high prices amongst collectors.
As we became more and more industrialized, every engineer had slide rules and every math student used them. Rule is unused and still sealed in factory plastic. In my case, I beat the rest of them by getting rid of mine in one fell swoop by giving them to a museum. Slide Rule Distinctive features: Slide rule - very widely used, mainly for scientific calculations, before electronic calculators became cheap. One knob rotates the dial on the log side with respect to a small fixed needle seen just below lefthand knob aligned with '1'. On the downside, these approximations could hide mistakes and lead to gross errors.