Sight-line holding a stone: wire, stone and cardboard	Horizon: paint, plastic film, and Dutch metal	Desert landscape: ink wash on paper	Perspective model: ink, glass, cardboard and mirror	Parallax viewer: cardboard, glass, plastic and gold leaf
Displaced horizon: graphite and crayon on paper	Displaced mountain: ink on paper	Mirrored alignment device: glass, graphite, cardboard and gold leaf	Horizon and ellipse: graphite on paper	Planar surface with objects: graphite and paint on paper
Landscapes: ink, plastic sheet	Parallax viewer: glass, gold leaf and cardboard	Horizon alignment device: cardboard, wood, and thread	Horizon with object: chalk on paper