Speculum anni, or, An almanack for the year of our Lord God 1687 [electronic resource] : being the third after bissextile or leap-year and from the worlds creation 5690 : wherein is contained the principal aspects of the planets, eclipses, terms, both at London and Cambridge, inclination of the air with other things of note : calculated properly for the famous university and town of Cambridge, where the north pole is elevated above the horizon 52 degr. and 12 min. but may indifferently serve for any place within this kingdom.