William B. Slaughter was appointed to replace Horner.

The evidence

• “Horner, had been removed and his place given to William B. Slaughter, by appointment, dated February 16, 1837. Now there were two otherchanges made.”

  1879-history-of-rock-county/01-wisconsin-antiquities-indians-territory.md, PDF p. 42 / book p. 46

  Butterfield, C. W., et al. The History of Rock County, Wisconsin: its early settlement, growth, development, resources, etc. Chicago: Western Historical Company, 1879. Cornell University Library via the Internet Archive, archive.org/details/cu31924028871585.

  Grade A: Found on a page of one of our sources