In October 1924 the City of Chicago Health Department sought to promote the dietary value of milk and increase its consumption by using it to fuel the locomotive of a passenger train. The train consisted of five cars in addition to the locomotive. It ran for about 10 miles and carried around 200 passengers.

"Had the value of milk as a food been brought before the public by customary methods, only thoughtful persons in the community would have received and understood it; but when the Commissoner of Health dramatized the statement that 'milk is to your body what coal is to the locomotive,' widespread interest was aroused..."

The milk was made into a powdered cakes in order to be fired, shown being tasted by one of the gentlemen in the above image. This leaves us with one important question....what does one wash their milk cake down with?

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.