Matthew MacFadzean plays Mr Hobson in this episode and has played as George Crabtree in the Murdoch's Mysteries movies.
Dr Grace goes to a reading of "The Wonderful Wizard of Oz," which was published on May 17, 1900, and the Inspector's friend had a $4 Dominion of Canada bill printed on May 3, 1900. Therefore, this episode took place after mid-May 1900.
This episode takes place in 1900.