Another work where a little Dada seeped in was [Ramón] Sender's Tropical Fish Opera, where an aquarium had five lines painted on it and the musicians seated around it played the notes made by the fish as they swam by. At one performance some of the fish refused to move, and the violinist Nathan Rubin dutifully played one unvarying tone, while the clarinettist Larry London, bored, began improvising, "at which Rubin swung around and barked 'What's the matter, London? Can't you read fish?'".