Conversation so far:
Where did Camille Saint-Saëns begin Camille Saint-Saëns's early career?
On leaving the Conservatoire in 1853, Saint-Saens accepted the post of organist at the ancient Parisian church of Saint-Merri near the Hotel de Ville.
How long did he hold that position?
CANNOTANSWER.

Question: What else did he do?
Self-contained rewrite: What else did Camille Saint-Saëns do aside from the organist position?