The description and use of a new portable orrery, on a simple construction, representing the motions, and phn̆omena of the planetary system [electronic resource] : But more particularly the motions of the earth and moon round the sun; from whence the nature and causes of the vicissitudes of the seasons, days, and nights, solar and lunar eclipses, &c. are clearly and familiarly explained. To which is prefixed, a short account of the solar system, or the true system of the world. The fourth edition, improved, with an account of the new planet, and other recent discoveries by Dr. Herschell, &c. the probable causes why the comet did not return as lately expected, and embellished by two new copper-plates; on representing the instrument, and the other an accurate delineation of the moon. By William Jones, mathematical instrument maker.