This intriguing rather well-preserved contraption is an early rock moving machine which is on display outside of the Dufferin County Museum in Ontario. It's quite large.
I tried to find out a bit more about how it worked but there was no information. Apparently there are several others like it still in tact in Ontario. They are all based on some sort of geared system for lifting rocks using a team of horses. The wheels are helpful in straddling big boulders and hauling them off the field and then straddling a dry stone wall to deposit the rock carefully on top.
This looks easy. I just need to find a team of horses now