According to this National Park Service website:http://www.nps.gov/civilwar/search-regiments-detail.htm?regi...
The 4th Regiment, Minnesota Infantry was in the advance on and siege of Corinth, Miss., May 18-30. Pursuit to Booneville May 31-June 12. Duty at Clear Creek till August. Expedition to Rienzi and Ripley June. Moved to Jacinto August 5, and duty there till September 18. March to Iuka, Miss., September 18-19.
So it looks like Camp Clear Springs was around Jacinto. But you have to realize that the men could have just made up the name as something they liked and that it has nothing to do with any permanent location in Mississippi.
Good luck with your research!
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