Here's my take based purely on transcription:

State of Mississippi Calhoun County}
On this 6th day of October 1863 Before me [Joseph S. Ryan Clerk of Probate Court of said county] [personally appeared] [Euginia] Foster who being duly sworn according to [law deposes] and says she is the [widow] of John[ Foster decs {deceased} who was a private in Capt. Clarks Co 42nd Regiment Miss Vols Clarks company Miss.]….
NEXT: and that she makes this [deposition] for the [purpose] of [obtaining from] the Gov of the C.S.A.
(NEXT at the bottom) Sworn to [and subscribes before] me [J S Ryan Clerk] {not Joseph Clark}

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(and in the second document I can't read the Mans name of the Treasury Dept)
That’s a tough one, [Looks like the last name is “Calvet or Calvert” using the script final “t” with a flourish for emphasis. The first initial could be “T” “I” “Q” or “L”. I think “T” or “I” are most likely.

Hope this is helpful.
Ron Skellie