Here’s a ticket envelope from that four-year period between introduction of the Mid-Century Empire Builder and the addition of Great Domes to that train. The date on the envelope is 1953.
Click image to download a PDF of the envelope.
The beautiful illustration of green-and-orange trains in front of brownish mountains and purple skies required four print colors, which always makes me wonder why they didn’t just go for a four-color process that would effectively allow the use of far more colors. Perhaps the need to be restrained to just four colors was somehow considered elegant in the world of illustration.