Midgley Indicator, circa 1922

01

Artifact Overview

In the early 1920s, engineer Thomas Midgley worked with General Motors research head Charles Kettering to reduce engine knocks caused by uneven burning of gasoline in automobile engines. Midgley developed this indicator to measure engine cylinder pressure. The device recorded its readings on photosensitive paper. Midgley and Kettering ultimately discovered that adding tetraethyl lead to gasoline prevented knocks.

Artifact Details

Artifact

Indicator

Date Made

circa 1922

Creator Notes

Invented by Thomas Midgley, Jr., for the Dayton-Wright Division of General Motors Corporation in Dayton, Ohio.

Location

Not on exhibit to the public.

Object ID

00.1707.9

Credit

From the Collections of The Henry Ford.

Material

Leather
Wood (Plant Material)
Mahogany (Wood)
Velvet (Fabric weave)
Metal

Color

Black (Color)
Brown
Gold (Color)
Green

Dimensions

Height: 22.5 in (case)
Length: 13.75 in (case)
Width: 12.75 in (case)

Inscriptions

on top of indicator: MIDGLEY INDICATOR / PAT APP FOR / INDICATOR OFF/ PHOTOGRAPH OFF / GENERAL MOTORS CORPORATION / DAYTON-WRIGHT DIVISION / DAYTON, OHIO, U.S.A. / SERIAL NO 100 A