O. W. Watson was a Spokane, Washington photographer who did mostly northwestern scenery and town views. His operations were during the period 1890 to about 1908. His views are considered scarce, but they do show up from time to time especially in the western United States. Subjects know to have been photographed were many Washington state views, including rivers, bridges, parks, etc. He also had some Yosemite and Yellowstone views. Unfortunately there is very little surviving information about Watson’s enterprise.
He had three types of Yellowstone views. His low number series goes from #1 to at least #31 and were probably the first he issued of the park. They were copyright 1907. He then produced his 600 series which have at least 37 views. Also copyrighted 1907, they were likely his last Yellowstone set. (This may have been the year of the photogtraphy rather than the issue of the view). Watson also produced a few unnumbered views of the park. It may be that the numbered views were part of sets that he sold together and the unnumbered were sold individually.
601 Gateway Entrance, Yellowstone National Park.
Series 1907, by O. W. Watson Co.
25. Fish Cone. Yellowstone Park.
Firehole River and Bridge. Yellowstone Park.