A number of O.T. Frasch images in the range from 800 to 899 document the design and construction of the Smith Tower, which was at the time the tallest skyscraper in the world outside of New York City.
There are also quite a few unsigned photos in the range from 860 to 899 showing one or more parades held for the 1911 to 1913 Golden Potlatch celebrations. The writing on the photos is very distinctive; we're not sure why Otto did not sign them, when some of his Golden Potlatch images are in fact signed.
Decades with images:
A selected image from the range 800-899: