This is a lot of 5 stereoscope cards. Pictures taken of the Parliament buildings in Ottawa, Canada. One shows the site where the Chateau Laurier sits today. Another is an aerial view of the roof of the Parliament buildings, dated 1904, with an interesting write up on the back. Another is of the interior of the Parliament buildings.

One card has a chunk out of the bottom right corner. 

Please ask any questions that you'd like. I'm happy to answer them.