Blackwell Station is now known as Blackwell Missouri and is south of Desoto MO in North St. Francois County Missouri. It was a stop on the St Louis Iron Mtn Railroad and indeed a skirmish took place near there on Oct 15th, 1861 featuring parts of the 2nd MO Cav (Compnay C? someone better at units will have to help here!) under Solomon Kitchen.

Blackwell is in the extreme northwest corner of the county, near Big River on Highway CC.

It is located at Sec. 6, Twp. 38 N, R. 4 E.

Blackwell Station ... situated on the west bank of Big River and on the St. L. I. M. & S. R. R., 51 miles from St. Louis, had 1 store and 1 hotel. (--Gazetteer of Mo., p. 500.)

or

Place name: Blackwell or Blackwell Station
Description: A town in the extreme northern part of the county in Big River Township. The post office was listed as Blackwell's Station 1867-1886; since 1886, as Blackwell. Named for the owners of the land upon which the town was located, Lavinia Blackwell and Margaret Blackwell. (Postal Guide; Goodwin (1867); Campbell's ATLAS (1873); Miles, HIST. ST. FRANCOIS (1935) 580) See our JEFFERSON COUNTY HERITAGE p. 143-146 after Jeremiah Blackwell.
Source: Zimmer, Gertrude M. "Place Names Of Five Southeast Counties Of Missouri." M.A. thesis., University of Missouri-Columbia, 1944.

John R.