Caption: Flying white flags up front, CPR G1r "Pacific" 2203 is the westbound assist engine leading RS18 8777 and its freight westbound on the Galt Sub around Guelph Junction. In the steam era, a helper or "assist engine" was often needed for the westbound climb from Lambton/West Toronto to Orr's Lake. Upon arrival at Orr's Lake, the assist engine (usually placed in front of the road engine) would then uncouple and run back light power to Lambton for the next train out of Toronto to assist westward. 2200-series Pacifics like 2203 out of Lambton roundhouse were often assigned to these assist duties.

2203 was originally built at CP's Angus Shops in September 1906, and ran out her final years in the Toronto area before being scrapped in August 1960, at the end of the steam era. CP RS18 8777 on the other hand, would become a regular at Guelph Junction: rebuilt as RS18u 1861, it would be sold to the Ontario Southland Railway in 1998, repainted as OSRX 181, and assigned to the Guelph Junction Railway out of Guelph Junction.

Original photographer unknown (duplicate slide, Bill Price maybe?), Dan Dell'Unto collection.