In the early 1880's Bailey Willis was a geologist with the Northern Pacific Railroad (NPR) assigned to conduct reconnaissance of the coal and iron ore resouces in several northern states and territories, one area being the Washington territory and more specifically the Carbon River areas near and in the Mt Rainier National Park.
During some of his expeditions in the area he guided dignitaries, some of whom, along with Willis, advocated Mt Rainier be designated a national park similar to Yellowstone in 1872. That effort wouldn't begin until about 1893 and succeed in 1899.
As part of his work with the NPR he established and supervised the construction of trails into the upper Carbon River and Mowich Lake area, parts of which are part of the present day Carbon River road and Mowich Lake road (highway 165), and parts of which are parts of the modern day trails in the NP.
And as described in the essay, he often travelled to areas in the NP long before there were trails, again where there are trails today. He likely was the one of the few, if not the first, to see some of the places now accessed by established trails.
Bailey and others would convince the NPR to promote tourism in the northwest area, in part because of the ready access to it from Seattle and Tacoma, and the beauty of that part of the NP. The effort would fade because effort was put into the southwest area with the establishment of the Longmire resort and the popularity of the Paradise Valley.
From his travels in the area Bailey wrote a personal essay, "Among the Cliffs of the Northwest Spur", referring to the upper Carbon River and Mowich Lake area in present day Mt Rainier NP. The essay was never published and tucked away into his papers at the Huntington Library in Los Angeles.
I have transcribed the essay out of interest in his thoughts and experience. Clearly he was awed by the scenery. You can find the essay here which has a link to a PDF version. Some of the names of places in the essay have changed and some places were misidentified from later work to name places in the NP. I have inserted the current names in brackets in the essay.