That train is the M-10000, the first streamliner passenger train ever made. It had a gasoline engine (later changed to diesel) and was articulated, meaning the cars shared trucks (the wheel assemblies) rather than having thier own. The resultant weight savings from that plus the streamlining made the train very light and fast. Streamliners were all the rage then and their stylistic influence carried over to cars and such things as those streamlined silver toasters and irons and other appliances. Back then, streamlined meant modern, and these trains would bring thousands of folks to the stations to view them, so associating your product with them was a good way to get visibility. Not that it worked in this case.
I know all this because I'm a train buff and a volunteer for the Flying Yankee restoration project,
http://www.flyingyankee.com , another streamliner coming soon to a track near you (hopefully). The FY was the third streamliner on the rails (after the M-10000 and Burlington Zephyr, which is now on display at Chicago's Museum of Industry).