Astrologonaytis or, The astrological seaman : directing merchants, mariners, &c. adventuring to sea, how (by God's blessing) to escape many dangers which commonly happen in the ocean. Unto which (by way of appendix) is added, A diary of the weather for XXI. years, very exactly observed in London: with sundry observations made thereon. By John Gadbury, student in physick and astrology.