Although this pre-war booklet has a nice four-color photo on the cover, all of the interior photos are black-and-white. Despite the lack of color inside (other than some yellow trim), the booklet is a good balance between showing the sights of Yellowstone and conveying an impression of the transportation and lodging facilities people will enjoy during their visits.
One surprise to me is a photo of the Geyser Water Swimming Pool, a natatorium that once stood near Old Faithful but was torn down in 1951. The booklet also pictures sunbathers, apparently near the pool, looking completely unconcerned that Old Faithful is going off in the background with almost no one watching. Of course, today the crowds on warm summer days are overwhelming.
Page 19 has the above photo of tourists looking at a stream that has cut the Northern Pacific monad logo into the landscape. The booklet says the stream is between Yellowstone Lake and Canyon. The postcard below, whose photo is copyrighted 1917 (though the card itself is from after 1930), identifies this stream as Trout Creek.
Google maps shows a car park overlooking Trout Creek where some former stream meanders once formed the logo. They have since been cut off. In retrospect, it is amazing that the creek remained unchanged from 1917 to 1941–or possibly it had changed and the booklet just used an old photo.
The booklet advertises a 2-1/2-day tour of the park, including food, lodging, and transportation within the park, for as low as $33.50–but that’s $550 in today’s dollars. Extra days were $4.50 a day ($75 today), presumably for food and lodging but not transportation.