Excerpted from Papers And Addresses of the Kent (Ontario, Canada) Historical Society:
The following is a short account of the early settlement of McKay's Corners, situated on lots 19, Town line range Harwich and Howard.
The town line between Harwich and Howard was all opened for travel from Lake Erie to the River Thames between the years 1820 and 1835. There was a tier of lots surveyed on each side of the town line called the town line range survey, on the Harwich side from the sixth concession Lake Erie survey to the sixth concession River Thames survey and about the same distance on the Howard side.
The first settlement on the Town Line commenced about Troy in the early twenties. The Rushton family settled on Lots 7 and 8 Howard side in 1825, which afterwards received the name of Rushton's Corners. The Camerons on the Howard side in 1830.
Here's a publication by Frank Cameron about the area, entitled "1858-1941, Botany Church : records and memories of Botany Presbyterian Church and its successor St. John's United Church."