Mathematical Charts and TablesConversion Tables
As has been suggested already, instructive mathematical charts introduced unfamiliar units of measure. A number of handy tables also were produced to assist in conversions. Perhaps the earliest such chart in the collections dates from about 1814, and is designed to convert from units divisible by twelfths to decimal units. The size of conversion factor and the way the numbers are written suggest that it was made to convert from Massachusetts pounds and shillings to U.S. currency. By the mid-20th century, the dollar prevailed throughout the United States, and Americans were more concerned with understanding foreign currencies when they traveled abroad. Toward that end, some purchased a slide chart called the UNICON, which allowed them to convert between dollars and numerous foreign currencies when they knew the exchange rate.
Engineers have long needed to perform conversions as part of their work. In the first half of the 20th century, manufacturers sometimes distributed small advertising cards that listed decimal equivalents of parts of an inch. Larger tables might list a large number of useful conversion factors. New efforts to introduce metric weights and measures in the United States in the 1970s led to the distribution of a range of cards and slide charts that eased conversions. These were distributed by organizations ranging from the federal government to a manufacturer of outdoor clothing and camping supplies to a producer of food emulsifiers and flavorings.
"Mathematical Charts and Tables - Conversion Tables" showing 1 items.
- In the 1970s, after metric units of measure had been adopted in Canada and Great Britain, some people in the United States advocated adoption of the metric system. A variety of special tables were made to help Americans convert between systems of measurement. This slide chart is one of them.
- The paper cardboard sleeve is joined with adhesive and printed in red, yellow, pink, black and white. The front contains a table for converting inches to millimeters, another for converting pints to liters, a third for converting feet to meters and a fourth for converting gallons to liters. The reverse has tables for miles/kilometers, ounces/grams, pounds/kilograms and oF/OC.
- A mark on the front reads: Metrics (/) made easy. Another reads: INCH/METRIC DIGITAL DIAL (/) A product of (/) Danatron (/) Corporation (3198 ‘C’, Airport Loop Drive, Costa Mesa, CA 92828. A mark on the edge of the slide reads (as best as can be deciphered): Copyright 1977 Nelson Taxel Woodmere N.Y. 11598 Printed in U.S.A.
- The object was found in the collections of the Division of Work and Industry of the National Museum of American History.
- Currently not on view
- date made
- Danatron Corporation
- ID Number
- catalog number
- nonaccession number
- Data Source
- National Museum of American History, Kenneth E. Behring Center