score:6
This is a very interesting question. I tried to track down references to this phenomenon and so far I found one, in a book by Caroline Kirkland: here on p.13 in a story called Land Fever a character says "Well! you're a land-shark, then - swallowin' poor men's farms." Seems like O. Henry was describing a fairly common occurence.
Upvote:3
Speaking as a resident of a neighboring state (which had its own land issues), while this was perhaps entertainingly phrased, nothing in there sounds at all unlikely or outlandish. Assuming (which I think is safe) that his "vast hegira" happened piecemeal rather than all at once, I find nothing whatsoever in there difficult to believe.
What is left is an entertaining exposition on the prevalence of endemic surveying errors (and the ability of the rich/well-connected to get such errors resolved in their favor). This most certainly was the case in eighteenth and nineteenth century America, not only on the local level, but even as regards to state boundaries.
The book How the States Got their Shapes goes into this in detail. If you ever wondered about the odd little straight-edge bends some state boundaries have (see Alabama), more often than not a surveying error was involved somewhere. Just thumbing through the first third of the book, I found surveying errors having a hand in the modern borders between five pairs of states, and out and out corruption probably involved in two. The border between Iowa and Missouri was particularly interesting, in that it involved both.
Upvote:5
I worked in land development in Texas and studied surveying in college. Excess land in old surveys was a very common problem mainly because the methods used to conduct the surveys in the old days was not near as precise as they would become later. The professors even mentioned the exact term "feeling their oats."
They had a tendency, when land was cheap and unoccupied, to add twenty to 100 varas to each mile of line to make certain that no one was cheated; hence, a supposed section of land has often been found to contain from one to 100 acres of excess. [1]
These mistakes did end up causing serious title issues regarding the land that required intervention from authorities to right.
Their inaccuracies, which gave rise to land vacancy and land excess, resulted from crude equipment, incorrect methods, lack of training, and carelessness... Because of these inaccuracies, the Texas legislature has made several reforms, particularly the Statute of Limitations, to protect settlers who located on land sometimes considerably distant from that described in their patents, and House Bill No. 9 of the Forty-sixth Legislature, June 19, 1939, to protect owners of excess land from unscrupulous land grabbers. [1]
In Texas just because a survey has excess acreage does not automatically invalidate the patent, even for the excess, see Foster vs Duval Ranch. The problem was though that later land grabbers had more money and power and were able to push their agenda through to the detriment of the original title holders. Many of these later titles were in fact invalid, but the actual owner of the land did not have the money, influence, etc... in order to contest it and therefore had their land essentially stolen from them. The time period O'Henry is referring to happened before the the legislative protections for the original patent holders which did not happen till the early to mid 20th century.