"Those signs said 'keep to extreme right do not stop or pass on curves'. What I really want to know is the small writing on the bottom of it!"
"I was recently given a lot of these all the pictures that my great grandfather drew... That is my great grandfather’s name bowman [on the bottom right]."
Ben Carscallen, February 14, 2020: [Mushroom Rock is]on the other side of the bluff, same rock bluff/cliff, but different area of it. Mushroom Rock is a part of the “half tunnel” that was cut there. They get confused all the time.
Chris Meinicke , February 14, 2020: "yes it does look like a mushroom from this angle. I have a couple of old postcards of Bishop's rock."
Ben Carscallen, February 14, 2020: "There's a couple color views from the left on the hill from the trees, then there’s one about where the screenshot is, then a couple horizontal views from a little farther down the road. Other than that I haven’t seen any other views of it."
http://columbiariverimages.com/Regions/Places/bishops_cap.html
Bishop's Cap rock formation in the Columbia River Gorge east of Portland, Oregon, 1927
(http://photos.salemhistory.net/cdm/ref/collection/orarc/id/193)