Pickett N500-ES Log Log Duplex Slide Rule

This duplex aluminum linear slide rule is coated in yellow ("eye saver") plastic and is held together with stamped aluminum contoured posts. The nylon cursor has a convex lens. The front of the base has +LL1, -LL1, A, D, DI, and K scales, with B, T, ST, S, and C scales on the front of the slide. The left end of the slide is marked: MODEL (/) N-500-ES (/) HI LOG/LOG. The right end of the slide has the Pickett logo used between 1964 and 1975 ("PickETT" with a triangle dotting the i) and MADE IN U.S.A.
The back of the base has +LL2, -LL2, DF, D, +LL3, and -LL3 scales, with CF, CIF, L, CI, and C scales on the back of the slide. Both ends of the slide are marked with the Pickett logo, with ALL METAL (/) SLIDE RULES on the left end and ©1962 on the right end.
There is a black leather case lined with black plastic and marked below the slot for the flap with the Pickett logo in gold. The case has no belt loop. The case fits into a white, green, and black cardboard box. Compare to the box collected with 1995.0126.02. The bottom of this box has a flap marked: PickETT (/) WORLD'S MOST ACCURATE (/) SLIDE RULES. A blue and white sticker on the flap describes the slide rule's features: N500 (/) HI-LOG SPEED RULE (/) THE SUPERIOR TRIG/LOG LOG RULE FOR ESSEN- (/) TIAL ENGINEERING AND TECHNICAL NEEDS (/) All Metal construction for highest accuracy and lifetime (/) performance (/) 22 Key Scales with a comprehensive 60-inch log range (/) With Carrying Case and complete instruction manual (/) Lifetime Guarantee.
The guarantee, with a registration card, is in the bottom of the box, along with the plastic bag that originally contained the slide rule inside the case. The registration card indicates that this example's serial number is A103202 and that the company's headquarters were in Santa Barbara, Calif. The company moved to Santa Barbara in 1964. Along with the logo, this suggests the slide rule was made in the mid-to-late 1960s. Students typically purchased this model in college and continued to use it in their careers.
Reference: International Slide Rule Museum, "Pickett," http://sliderulemuseum.com/Pickett.htm.
Currently not on view
date made
after 1964
Pickett Industries
place made
United States: California, Santa Barbara
Physical Description
aluminum (overall material)
leather (case material)
paper (case material)
plastic (cursor material)
overall: 3.5 cm x 9 cm x 34 cm; 1 3/8 in x 3 17/32 in x 13 3/8 in
ID Number
catalog number
accession number
Credit Line
Gift of Thomas A. Bair II
Rule, Calculating
Engineering, General
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Slide Rules
Data Source
National Museum of American History, Kenneth E. Behring Center


"That seems correct for that model later on, in 1962 the N-500 Log Log was made in Chicago, IL. It also reads HI directly to the left of the word "Log "over and under a horizontal line. I have still have one with black leather case and instructions."

Add a comment about this object