June,

Try this link at the Tennessee and the Civil War website:

1ST TENNESSEE VOLUNTEER INFANTRY REGIMENT, U.S.A.
http://www.tngenweb.org/civilwar/usainf/usa1inf.html

Your veteran is listed here:
http://www.tngenweb.org/civilwar/rosters/inf/inf1/cof1.html

LEWIS MOSIER
Rank: 1 Lt
Age: 36
Enlisted: Aug 9 61 Mustered: Aug 20 61
Remarks: Resigned Jan 10 62

This man also received a Veteran's pension and his wife applied for and received a widow's pension.

His service record and pension files are available through the link at the bottom of this message.

I hope this helps.

Jim Martin