Mr. A.F. Miller's observatory in Toronto.
This photo was published in the RASC Selected Papers and Proceedings, 1902-03.
Links:
[1] http://www.rasc.ca/category/archivetags/1902
[2] http://www.rasc.ca/category/archivetags/afmiller
[3] http://www.rasc.ca/category/archivetags/observatory
[4] http://www.rasc.ca/category/archivetags/photo
[5] http://www.rasc.ca/category/archivetags/toronto
[6] http://www.rasc.ca/category/image-galleries/national-archives/archives-1900s