Geometrical dyalling: or, dyalling performed by a line of chords onely, or by the plain scale. : Wherein is contained two several methods of inscribing the hour-lines in all plains, with the substile, stile and meridian, in their proper coasts and quantities; being a full explication and demonstration of divers difficulties in the works of learned Mr. Samuel Foster deceased, late professor of astronomy in Gresham Colledge,; [sic] also a collection of divers things from the works of Clavius and others. Whereto is added four new methods of calculation, for finding the requisites in all leaning plains, with full directions suited to each method for placing them in thier proper coasts, without the help of any delineations. Also how by projecting the sphere, to measure off all the arks found by calculation, and to determine what hours are proper to all kinde of plains, omitting superfluity. Lastly, the making of dyals from three shadows of a gnomon placed in a wall at random, with a method of calculation suited thereto, and divers ways from three shadows, to finde a Meridian-line. Written by John Collins of London accomptant, philomath.