Dennis Callegari has been a science writer and technical writer since 1988. He is the author of Cook’s Cannon and Anchor (Kangaroo Press, 1994), and is a devotee of clerihews and h...ver maisDennis Callegari has been a science writer and technical writer since 1988. He is the author of Cook’s Cannon and Anchor (Kangaroo Press, 1994), and is a devotee of clerihews and historical mysteries.ver menos