The National Park Service surveyed the Cascades in Washington for a potential National Park way back in 1937 during FDR’s administration.
Here’s an album of photos produced as a supplement to that report, and a selected photo showing the team, with a close-up. The photographer is not identified, although many of the images in the album are attributed to L. D. Lindsley, grandson of David Denny and employee of Edward S. Curtis.
The sad story is that WWII interrupted all interest in new National Parks just after this study was done, and thus only a small fragment of the North Cascades gained Park status much later, not till ’68.
Also, in ’37 the timber industry was still smarting from FDR’s new Olympic National Park (a larger version of Teddy Roosevelt’s Mt. Olympus National Monument) that “locked-up” vast areas of Olympic timber, so the timber barons lobbied hard against any Park in the Cascades, other than the little postage-stamp square around Rainier.