L'Affaire Tournesol
Calculus maintains a laboratory at Marlinspike Hall, in which he conducts various experiments. He is fairly protective of his work, on occasion hiding his scientific endeavours from Tintin and Haddock (which gets him into trouble in "The Calculus Affair"). His lab is also stripped of all its apparatus in the same book. On an earlier occasion, during his efforts to find an antidote to Formula Fourteen in "Land of Black Gold", Calculus almost destroyed half of Marlinspike in an explosion.