Cory, I believe that when the army first came to the area, they did not survey from stone marker or bench mark as nothing else existed in the valley. The army merely surveyed a military road from Barrs landing (sp) below the rocky ledge on the Yellowsone, (this was as far as the steamships could come up the river unless it was at the peak of high water in June) to Fort Keogh. This established a road for the military to carry goods on into the fort by wagon (probably a matter of about ten miles). Since the military road was established when people began to settle in the valley, all property lines were established off of that. More than likely all of the merchants, whiskey traders and so forth in old Milestown lined up along that same military road. No one bothered to check for accuracy. This could be the reason true north-south lines do not exist. In addition, when the railroads came to the area the government used free land as an incentive for them to bring their rail lines in this area. The railroads were granted every other section either north or south of the railroad for fifty miles. This was not done on an accurate survey, but merely roughly. When the the USGS tried to survey the area in the early sixties they took some readings and everything in this end of the valley was off, They weren't going to try to rectify a mistake that had endured that long. I could be wrong, but check with someone who has surveyed land in this area for a long time, and he will probably have some version of the story.