40. Measuring Time

Short Stories
of Science and Invention

A Collection of Radio Talks by
Charles F. Kettering

Weekly, from September 1942 to July 1945, Charles F. Kettering gave five-minute intermission talks about Science and Invention during the radio broadcasts of the General Motors Symphony of the Air.

Kettering invented the first automobile self-starter, and for 31 years directed a research laboratory for General Motors.

These radio talks are a fascinating legacy from the mind of a prolific inventor. The obvious anachronisms now add a historical perspective of the war-time period in which they were written.

These web pages now preserve some of the most popular stories for a new generation to read The text and art come from a General Motors booklet of selected talks. (Reprint, March 1959)

40. Measuring Time
A Radio Talk by Charles F. Kettering

As we approach the end of 1943, the question of measuring time comes to our minds. Five hundred years ago people did not know the cause of the day and year.

For centuries men believed the earth to be the center of the universe - and that the sun, moon and stars all revolved around it.

Sun Dial

     Calculating the time of the year, assumptions were very difficult. All this was changed by Copernicus about the time Columbus discovered America.

     But long before the telescope and other astronomical instruments were invented, this Polish scientist and astronomer proved by simple observation and calculation that the sun is the center of our universe - and that the day is the result of the earth's rotation about its axis, and the year of its journey around the sun in its orbit.

     This new idea explained the changes in the length of night and day and winter and summer, but left the need for a method of measuring hours - minutes - and seconds unfilled.

     Devices of many kinds were constructed and I know of nothing that has tested man's inventive ability more than time-keeping.