Slide Chart, Heat Gain Calculator

This orange and black paper device has a set of tables printed on both sides of a piece of cardboard that slides between two other pieces of cardboard that are riveted together. The whole thing fits in a cardboard envelope. The tables are used to calculate the total heat gain from light shining through windows and other glass in a building. The instrument was distributed by Libbey Owens Ford Company, a glass firm in Ohio.
A mark on the envelope and the object reads: HEAT GAIN CALCULATOR; A paper sticker attached to the envelope reads: Display Copy Only (/) Please do not remove. A mark on the back of the instrument in the bottom right corner reads: ... 1975, PERRYGRAF Div., Nashua LA. CA 90064 Printed in U.S.A. A mark on the front left corner reads: LOF (/) GLASS (/) 811 MADISON AVENUE (/) TOLEDO, OHIO 43695. A mark on the front of the instrument reads: LIBBEY (/) OWENS (/) FORD (/) COMPANY.
Currently not on view
Object Name
mathematical chart
date made
Perrygraf Division, Nashua
Physical Description
paper (overall material)
metal (overall material)
overall: .3 cm x 28.5 cm x 18 cm; 1/8 in x 11 7/32 in x 7 3/32 in
place made
United States: California, Los Angeles
ID Number
nonaccession number
catalog number
Science & Mathematics
Mathematical Charts and Tables
See more items in
Medicine and Science: Mathematics
Mathematical Charts and Tables
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Jack Warner
Additional Media

Visitor Comments

Add a comment about this object

Submit a comment or ask a question about this object using the form below. Submissions are moderated and may receive a curator response. Please note that we cannot evaluate or appraise your personal artifacts. For other questions or general inquiries please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Enter the characters shown in the image.