Wind Chill Calculator, a Slide Chart

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. Holubar Mountaineering Ltd. of Boulder, Colorado, a manufacturer of outdoor clothing and camping supplies, distributed this cardboard slide chart. One side has a wind chill calculator. This had twelve columns of numbers with an actual temperature (given in both degrees Fahrenheit and degrees Celsius), at the head of each column. Figures in the column then gave the equivalent wind chill temperature for wind speeds in miles per hour (with the Fahrenheit scale) and in kilometers per hour (with the Celsius scale). Cold dangerous to health is indicated in shades of blue.

The reverse side of the chart has columns for converting from metric to English measures of length, mass, volume, and area. A number line has Fahrenheit temperatures on the top and Celsius temperatures on the bottom.

A mark on the sliding piece reads: GRAPHIC CALCULATOR CO., Barrington, Illinois 60010 Made in U.S.A. 12-76 -2349.

Currently not on view