Pickett Model N600-ES Log Log Speed Rule
Engineering; Mechanical Engineering; Mathematics
Physical Description:
The Pickett Model N600-ES Log Log slide rule is constructed using three yellow painted aluminum bars. The “ES” in the model name means “Eye-Saver” and refers to the yellow painted construction. The two outer bars are called the stators and are attached by a brace on both ends. The braces create a gap between the two stators where the third aluminum bar, called the slide, fits into the grooves between the two stators. A clear plastic cursor slides along the outside of the stators. The cursor has a vertical hairline marker on both sides of the slide rule for lining up the scales between the slide and stators. The upper stator has LL1 and A scales on the front side and LL2 and DF scales on the backside. The lower stator has D, DI, and K scales on the front side and D and LL3 scales on the backside. The slide has B, ST, T, S, and C scales on the front side and CF, Ln, L, CI, and C scales on the backside. The scales are usually logarithmic with a few exceptions such as the L and Ln scale which are log operations with a linear scale. The index of a scale is the furthest left number for the left index or the furthest right number for the right index. The scale ranges and operations are described under inscriptions.
Functional Description:
The Pickett Model N600-ES Log Log slide rule is a duplex slide rule. A duplex slide rule has scales on both sides of the slide rule and a dual-faced cursor. The dual-faced cursor allows for relating one side of the scale to the other side for a greater number of calculations. Logarithmic scales have a multiplication and division property discovered by William Oughtred in 1630 that allow for the operations of multiplication and division instead of addition and subtraction of linear scales. Multiplication is the simplest operation on a slide rule using the two fundamental scales, C and D. To multiply two numbers, x and y, the left index of C is positioned over x on the D scale. Then the cursor is position over y on the C scale. The value of the cursor on the D scale is the solution to x multiplied by y. The decimal place may need to be adjusted to get the correct order of magnitude since the C and D scale has values ranging from 1 to 10. The other scales are used to perform different operations such as squares, reciprocals, exponentials, and sines, cosines, and tangents.
Gideon Hoekstra, Nick Renke, Donovan Doran, Erik Madson
1962
English
Picket Model 1000 Slide Rule
Mathematics
<span style="text-decoration:underline;"><br /><span>Physical Description:</span></span> The Pickett 1000 slide rule is made of three rectangular bars of aluminum alloy coated in plastic with grooved slides. Two bars are connected at the end with braces that are mounted to the flat side of the bars and the third bar is free to slide between them, held in place by slide tension springs. The two outer bars are called stators and the inner bar is referred to as the slide. The slide rule also has a courser made of two flat lenses held together by aluminum above and below the upper and lower stators. Each bar of the Pickett 1000 slide rule has at least one scale on it. The front side of the slide rule has the DF scale on the upper stator CF, CIF, CI and C scales on the slide and D and L scales on the lower stator. The back side of the slide rule has an A scale in the top stator B, T, ST, and S scales on the slide and K and D scales on the lower stator.<br /><span style="text-decoration:underline;"><br />Functional Description:</span> <span>Slide rules work on a system of logarithms. In order to do multiplication the slide rule adds two logarithms and takes the antilog to determine the answer. Because the slide rule uses logarithmic scales, the operation is simplified. If the user wanted to multiply two numbers together they would move one of the indices on the C scale to the first number that they wish to multiply on the D scale .They would then move the cursor to the second number in the multiplication on the C scale and look at the corresponding number on the D scale. So, if you wanted to multiply 2 and 4 you would move the left index of the C scale to the 2 on the D scale, move the cursor to the 4 on the C scale and see that the answer Is 8. To do division the inverse is done. To find the square and square root the A or B scale and the D scale are used. Locate the number of the square root you want to find using the cursor, when found the corresponding number on the D scale is the answer. To find the square the inverse is found. cube and cube root K scale and the D scale are used. To find the cube root take the number and find it on the K scale read the corresponding number on the D scale. To find the cube the inverse is performed. Scales available on the slide C and D used for multiplication and Division, CF and DF used for multiplication and division when the C and D scales run out. The CI and CIF scales are the inverse of the C scale and CF scale respectively. The S T slides are used for sine and tangent of greater than 5.7 degrees while the ST slide is used for degrees less than 5.7 degrees. The A and B scales are used in the calculation of squares and square roots. The L scale is used for the Log base 10 of a number.</span>.<br /><span><span><br /></span></span>
Trevor Cretney, Adam Kausch, Matthew Luebke, and Adam Miller
International Slide Rule Museum. ISRM is the world's largest free digital repository of all things concerning slide rules and other math artifacts. There are over 7000 Images or PDF's in the ISRM Galleries">. Web. 22 Mar. 2017. <http://sliderulemuseum.com/SR_Scales.htm>.
Konshak, Mike. Pickett Chronology. JPG.
Hartung, Maurice L. How to use the Ortho-phase duplex slide rule. Pickett & Eckel, 1948. PDF.
1957
English
physical object
United States