President William McKinley and the Grim

[Caius Marcius]

Very strange story I just came across in a volume titled First Dogs: 
American Presidents and Their Best Friends (by Roy Rowan and Brooke 
Janis) a history of White House canines).  On September 6, 1901 
President William McKinley, on his way to the Pan American Exposition 
in Buffalo, paid a side visit to Niagara Falls. A photo showed 
McKinley observing the Falls while a large black dog stood just off 
to his side. The identity of the dog has never been established. A 
few hours later McKinley was fatally shot by Leon Czolgosz.

I was not able to find the photo online, but it may be found in the 
above-mentioned book, on page 65. 

    - CMC