Institutions of astronomical calculations; : containing a survey of the solar system, wherein all its dimensions of the distances, diameters, magnitudes and velocities of the sun, the earth, the primary and secondary planets, the comets and the stars are computed in English miles from the late discovered parallax of the sun, by the two last transits of Venus. : With a description of two new pieces of mechanism for exhibiting artificial views of such transits. : Embellished with two copper-plates