Brilliant guess, Gene, but it's not William Sprague.
Hint #1: Both Abraham and Mary Lincoln dealt with this gentleman.
Hint #2: His name is well-known!
I very much apologize for erroneously posting a photo of the sought-after gentleman's son due to a misleading caption. This is (guaranteed) the correct likeness. I was delighted to discover one (strangely only on...) "younger image", thus the mistake...anyway, the hints might even be correct for father and son (hint #2 definitely!!!). Sorry again!