This cairn is found in the cemetary around Holy Trinity Anglican Church and cemetery. It commemorates all that fought in the Battle of Chippawa. I was not able to find any specific details about this cairn online but there is some info on the cairn itself. There is a much larger cairn/monument in Battlefield Park along the Niagara Parkway with some caches around it to find. ;)
To find the next stage;
Go to the coordinates given and read ALL of the plaques on this cairn.
Find the plaque that specifically mentions the American forces. Count the number of old cannon balls on the top of the cairn. Take that number and multiply it by 7.5 (let's call this number C for cairn)
Go the the opposite side of the cairn and face away from the cairn. You should see a large tree and an OLD fence. Walk "C" meters towards the tree/fence and you should see a unique and cracked head stone.
Once at the unique headstone, read what you can of the lettering.
You will need some info off of this headstone to calculate the distance to the final. Please determine the name of the "affectionate son". His full name is 12 letters long. Please use the first 9 (nine) letters - convert letters to numbers (let's call this "H for headstone). To confirm your number is correct, the checksum of "H" is 16.
Project a waypoint from the headstone at 334 degrees a distance of "H"meters.
You are looking for a metal thermos that has been cammoed.