Catalogued
Andrews pitchfork
- Made by
- Alan Hall Andrews, after George Fillmore Swain via Roger Babson
- Year
- mid-20th century
- Field
- Economics and markets
- Kind
- Computing chart
- Room
- Change over time — Placed by reading its description, not yet studiedCould also hang in: Charts that compute
121 other forms share this skeleton
Source
Andrews, Action-Reaction Course
Attribution less certain: contested, or no single inventor recorded