Click image to download a PDF of this coaster or doily.
Second, it is much larger: 5 inches in diameter instead of 3-1/4. What kind of drinks are served in glasses large enough to need that big of a coaster? More likely, it is not really a coaster but a doily placed under ice cream and other dishes in the dining car.
Apparently, similar doilies were used in the Traveller’s Rest car–at least, the one above is for sale on ebay and is supposed to be 5 inches in diameter. The same seller also has the below NP coaster which, like the others previously shown here, has ink printing and is pressed paper and is only 3-3/4 inches but, unlike the others, is square.
So how old is the first doily shown above? The fact that it has “Northern Pacific Railway” instead of just “Northern Pacific” on the herald shows it is post-war. Since it seems to be common–one dealer recently offered a lot of more than 100 on ebay–it is likely that it was used right up to 1970, when Northern Pacific merged into Burlington Northern.