Hi Dennis, A recruting sargeant in trhe 1830's fits with the post Waterloo shako & gold sash
Regarding Thomas Williams at Waterloo - my friend has come up with the following -
"not sure that I can do very much to help but you're welcome to what I have got.
I have recorded 190 soldier with the surname of WILLIAMS as being at the Battle of Waterloo: 25 of them have the forename Thomas!
Of these 25; 6 were in the cavalry; 11 were in the infantry; 4 were in the corps and 4 were either killed in action or died subsequently.
Amongst the remaining 21 there are 5 NCO's: a Trumpet Major in the 18th Hussars; a Sergeant in the 2nd Foot Guards (Coldstream); 2 Sergeants in the 3rd Foot Guards (Scots) and a Sergeant in the 95th (Rifles).
Your man's uniform would exclude the Rifles and his rather rotund stature would probably exclude the cavalry; which just leaves the three Guardsmen as possibilities and looking at his stance and apparent demeanour, one of these could well be a possibility! Both of the Scots Guardsmen and the Trumpet Major were in receipt of the MGS medal as well as that for Waterloo.
Obviously he may not have been a sergeant at Waterloo, as this is some years later and he may have been promoted since."
May not help much - but it's another step somewhere!
Brian