In the process of apportionment 435 memberships of the US House of Representatives are divided between 50 American states.
Each state has the right for one member in the House of Representatives, the rest of the seats are distributed accordingly with the congressional district, which is a territorial division that has its boundary based in the number of the population registered by the Census.
A congressional district allows the area to elect one member, if the population changes in one area it may change the number of seats that congressional district can elect. So after the Census is completed the legislative seats are reapportioned. The number of seats can increase or be lowered.
Keeping in mind the description of the stone point given in the story, we can state Marshall the rancher was looking at a Folsom point.
As it's known, a Folsom is a kind of stone point with a leaf-like shape which has a concave base and wide, shallow grooves/flutes running almost the entire length of the point.
They had to produce more and more crops to raise enough money to feed their families. Over time the money was cut down because of how much they produced. Kind of like clearance. They couldn't feed there families anymore so they sold or gave their farm away and moved to the city for better work