Lincoln surveys town site of New Boston [or Upper Yellow Banks] on Mississippi River, 100 miles northwest of New Salem, now in Mercer County. Plat filed July 12, 1836 shows proprietors as William Denison, William H. Denison, and Peter Van Bergen, agent for Elijah Iles. [Van Bergen and Iles, both of Springfield, are large speculators in farm land and town sites.] Record.

[Auction sale of lots is held July 12, 1836, day Lincoln's plat of town is filed for record. Sangamo Journal, 16 July 1836.]

Lincoln and James Erwin witness deed of William and Rachel Deniston who deed lots in New Boston to Elijah Iles of Sangamon County. They also witness deed of William and Rachel Deniston to William H. Denison for lots in New Boston. Warren County Deed Record, 1:310-11, 322-23, Warren County Courthouse, Monmouth, IL.