slide rule

---

close up of a slide rule

---

Size: 4256px × 2832px
Photo credit: © Zoonar/Knut Niehus / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: architect, board, calculator, computer, construct, construction, design, draw, drawing, instrument, line, machine, mathematical, mathematics, reckoner, rule, ruler, sketch, slide, slide-rule, slide-ruler