New Addition to the Tec Museum of Engineering

Tec Inc. Engineering & Design would like to thank Steve Kay of Holophane for his donation to our collection of antique engineering books. The second edition text book “Illuminating Engineering” edited by Cady and Dates is Kay’s second donation to the collection. He previously donated a second edition of the “IES Lighintg Handbook.”

The second edition of Illuminating Engineering was published in 1928. The text book was prepared for students and engineers. The book is divided into two main sections, Principles and Applications, then further sub-divided into addtional specifics. 

One interesting section of the book is the Reflection Factors of Colored Surfaces.  Pasted on to the pages are 32 color cards, similar to paint cards or Pantone samples. Each card has a hole punched through to allow the user to hold an object or sample behind the card and match it to the color.  Each color is assigned a Reflection Factor - the proportion of light reflected by walls and ceilings of various colors.


Night at the Museum

The Tec Inc. Museum of Antique Engineering Tools… OK, that’s not the real name, we don’t really have a name for the museum.  But we have a museum.  And it’s filled with antique engineering devices and old books.  Periodically, I will write a post highlighting one of the objects in the museum. 

This post will focus on the favorite display of most visitors to the museum, the giant slide rule.  We purchased the item from Don Leinweber when he decided to close his structural engineering practice a few years ago.  He had it hanging in his storefront window.  The giant slide rule originated as a teaching tool in school - probably hanging at the front of the classroom for the instructor to demonstrate it’s use. 

Edmund Gunter developed the first slide rule in the early 1600’s.  There were several variations and improvements over the years, and slide rules remained prevalent until the 1970’s when the electronic calculator became affordable.

If you really like Slide Rules, please visit the International Slide Rule Museum.