According to this ad for Western Electric, Electrical Prosperity Week was held from November 29 to December 4, 1915:
It was a national event that was held to showcase how indispensible electricity is to everyday life, and to show off some of its capabilities.
I haven't come across any reviews of how it all went down yet, but I'll be sure to let you all know when I do. In the meantime, and, in the spirit of electricity, let's all take a moment to appreciate those things we plug in and take for granted.
About the Author: Mary Karmelek is a production assistant for Nature Publishing Group and is currently working on Scientific American's Digital Archive Project, where she spends countless hours scouring articles and ads of decades long ago. She graduated with her MA in English from Fordham University in 2010 and currently resides in New York City. While her educational background is in gender and war trauma in modernist literature, Mary also has a keen interest in the historical and visual documentation of science, nature and medicine.