He painted the bar sign for the 'Cabaret des Assassins' in Montmartre, depicting a rabbit escaping from a saucepan. The place then became known as 'Au Lapin à Gill', later to be called 'Le Lapin agile' (which was famous for its literary clientele and their pranks), and which bears that name today.
Gill was a member Le Cercle des poètes zutiques which used to meet at Hôtel des Étrangers, rue Racine, which is now Hôtel Belloy Saint-Germain. Other members of the group were Ernest Cabaner, Charles Cros, Camille Pelletan, Arthur Rimbaud, Léon Valade and Paul Verlaine.
Gill was interned in the psychiatric hospital Charenton at Saint-Maurice in 1883, where he died two years later at the age of forty-four.