Cool! I love looking through old civic photos.
The City of Toronto Archives also has an extensive collection of digitized photos online.
City of Toronto: Archives: List of digitized photographs
It's a frustrating excersize to browse through but fascinating once you get going.
Once you've clicked on a Series link, click "Browse" where it says "Record consists of". That will open another window indexing the links to the individual photos of the series. When you click ona link, you'll get the details and a thumbnail. Click on that and you get a photo.
The one from a Health department survey in 1912 is entitled
Interior Occupied - Slum on the north side of King St. E.
This one is of a crowd looking at car accident in Christie Pits in 1910.