Apparently officers sometimes decided to fight on foot:
An anecdote about Major (Captain) Archibald Menzies:
“At the Battle [of Quatre Bras] on the 16th of June, a brave Major of the 42d Highlanders, preferring to fight on foot in front of is men, had given his horse to a little drummer-boy of the regiment. After some severe fighting with the French Horse Cuirassiers and Lancers, and after receiving several severe wounds, he fell from loss of blood near a brave private, Donald Macintosh, of his corps, who was mortally wounded at the same instant. (…) An officer of the Cuirassiers, at this time observing our poor Major still bestirring himself, road up, and stooping from his charger, aimed to dispatch him with his sword; our resolute Major seized his leg, and still grappled with him so stoutly, that he pulled him of his horse upon him. Another lancer, observing this struggle, galloped up, and, to relieve his officer, attempted to spear the Major, who, by a sudden jerk and desperate exertion, placed the Frenchman, in the nick of the necessity, in his arms before him, who received the mortal trust below his cuirass, and in this condition continued lying upon him, with his sword in his hand, for near ten minutes. (…) Another private of his regiment now came up, and asked his Major what he could do to assist him? –“Nothing, my good friend, but load your piece and finish me.” “But your eye still looks lively (said the poor fellow); if I could move you to the 92d, fighting hard by, I think you would yet do well.” With the aid of a fellow soldier, he was moved as the man proposed, and soon seen by an intimate friend, Colonel Cameron, commanding the 92d, who instantly ordered him every succour possible. (…) It is a pleasure to add, that the brave Major is still alive, wearing the honourable decoration and marks of sixteen severe wounds received in this unequal and arduous conflict, and lame too from a severe wound received at the storming of Badajoz.”
The whole anecdote is on my website, see link below.
Best regards, Geert