Some latitudes have no canicular daies at all; as namely all those which have more then 73 degrees of Northern Elevation; as the territory of _Nova Zembla_, part of _Greenland_ and _Tartary_; for unto that habitation the Dog-star is invisible, and appeareth not above the Horizon.
Unto such latitudes wherein it ariseth, it carrieth a various and very different respect; unto some it ascendeth when Summer is over, whether we compute Heliacally or Cosmically; for though unto _Alexandria_ it ariseth in Cancer; yet it ariseth not unto Biarmia Cosmically before it be in Virgo, and Heliacally about the Autumnal Equinox. Even unto the latitude of 52, the efficacy thereof is not much considerable, whether we consider its ascent, Meridian, altitude or abode above the Horizon. For it ariseth very late in the year, about the eighteenth of _Leo_, that is, the 31 of _July_. Of Meridian Altitude it hath but 23 degrees, so that it plaies but obliquely upon us, and as the Sun doth about the 23 of _January_. And lastly, his abode above the Horizon is not great; for in the eighteenth of _Leo_, the 31 of _July_, although they arise together; yet doth it set above 5 hours before the Sun, that is, before two of the clock, after which time we are more sensible of heat, then all the day before.
Secondly, In regard of the variation of the longitude of the Stars, we are to consider (what the Ancients observed not) that the site of the fixed Stars is alterable, and that since elder times they have suffered a large and considerable variation of their longitudes. [SN: _What the longitude of a Star is._] The longitude of a Star, to speak plainly, is its distance from the first point of numeration toward the East; which first point unto the Ancients was the vernal æquinox. Now by reason of their motion from West to East, they have very much varied from this point: The first Star of Aries in the time of _Meton_ the _Athenian_ was placed in the very intersection, which is now elongated and removed Eastward 28 degrees; insomuch that now the sign of Aries possesseth the place of Taurus, and Taurus that of Gemini. Which variation of longitude must very much distract the opinion of the Dog star; not only in our daies, but in times before and after; for since the World began it hath arisen in Taurus, and if the World last, may have its ascent in Virgo; so that we must place the canicular daies, that is, the hottest time of the year in the Spring in the first age, and in the Autumn in Ages to come.