Fourthly, (which is the Argument of Geminus) were there any such effectual heat in this Star, yet could it but weakly evidence the same in Summer; it being about 40 degrees distant from the Sun: and should rather manifest its warming power in the Winter, when it remains conjoyned with the Sun in its Hybernal conversion. For about the 29 of October, and in the 16 of Scorpius and so again in January, the Sun performs his revolution in the same parallel with the Dog-star. Again, If we should impute the heat of this season, unto the co-operation of any Stars with the Sun, it seems more favourable for our times, to ascribe the same unto the constellation of Leo. Where besides that the Sun is in his proper house, it is conjoyned with many Stars; whereof two of the first magnitude; and in the 8{th} of August is corporally conjoyned with Basilicus; a Star of eminent name in Astrology, and seated almost in the Ecliptick.
Fifthly, If all were granted, that observation and reason were also for it, and were it an undeniable truth, that an effectual fervour proceeded from this Star; yet would not the same determine the opinion now in question; it necessarily suffering such restrictions as take off general illations. For first in regard of different latitudes, unto some the canicular daies are in the Winter; as unto such as have no latitude, but live in a right Sphere, that is, under the Equinoctial line; for unto them it ariseth when the Sun is about the Tropick of Cancer; which season unto them is Winter, and the Sun remotest from them. Nor hath the same position in the Summer, that is, in the Equinoctial points, any advantage from it; for in the one point the Sun is at the Meridian, before the Dog-star ariseth; in the other the Star is at the Meridian, before the sun ascendeth.
What latitudes have no Dog-daies at all.
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. 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.
Thirdly, The Stars have not only varied their longitudes, whereby their ascents have altered; but have also changed their declinations, whereby their rising at all, that is, their appearing hath varied. What the declination of a Star is. The declination of a Star we call its distance from the Equator. Now though the Poles of the world and the Equator be immovable, yet because the Stars in their proper motions from West to East, do move upon the poles of the Ecliptick, distant 23 degrees and an half from the Poles of the Equator, and describe circles parallel not unto the Equator, but the Ecliptick; they must be therefore sometimes nearer, sometimes removed further from the Equator. All Stars that have their distance from the Ecliptick Northward not more then 23 degrees and an half (which is the greatest distance of the Ecliptick from the Equator) may in progression of time have declination Southward, and move beyond the Equator: but if any Star hath just this distance of 23 and an half (as hath Capella on the back of Ericthonius) it may hereafter move under the Equinoctial; and the same will happen respectively unto Stars which have declination Southward. And therefore many Stars may be visible in our Hemisphere, which are not so at present; and many which are at present, shall take leave of our Horizon, and appear unto Southern habitations. And therefore the time may come that the Dog star may not be visible in our Horizon, and the time hath been, when it hath not shewed it self unto our neighbour latitudes. So that canicular daies there have been none, nor shall be; yet certainly in all times some season of the year more notably hot then other.
Lastly, We multiply causes in vain; and for the reason hereof, we need not have recourse unto any Star but the Sun, and continuity of its action. For the Sun ascending into the Northern signs, begetteth first a temperate heat in the air; which by his approach unto the solstice he intendeth; and by continuation increaseth the same even upon declination. Why the Dog-daies be so hot. For running over the same degrees again, that is, in Leo, which he hath done in Taurus, in July which he did in May; he augmenteth the heat in the latter which he began in the first; and easily intendeth the same by continuation which was well promoted before. So it is observed, that they which dwell between the Tropicks and the Equator, have their second summer hotter and more maturative of fruits then the former. So we observe in the day (which is a short year) the greatest heat about two in the afternoon, when the Sun is past the Meridian (which is his diurnal solstice) and the same is evident from the Thermometer or observations of the weather-glass. So are the colds of the night sharper in the Summer about two or three after midnight, and the frosts in Winter stronger about those hours. So likewise in the year we observe the cold to augment, when the daies begin to increase, though the Sun be then ascensive, and returning from the Winter Tropick. And therefore if we rest not in this reason for the heat in the declining part of Summer, we must discover freezing Stars that may resolve the latter colds of Winter; which whoever desires to invent, let him study the Stars of Andromeda, or the nearer constellation of Pegasus, which are about that time ascendent.
It cannot therefore seem strange, or savour of singularity that we have examined this point; since the same hath been already denied by some, since the authority and observations of the Ancients rightly understood, do not confirm it, since our present computes are different from those of the Ancients, whereon notwithstanding they depend; since there is reason against it, and if all were granted, yet must it be maintained with manifold restraints, far otherwise then is received. And lastly, since from plain and natural principles, the doubt may be fairly salved, and not clapt up from petitionary foundations and principles unestablished.
But that which chiefly promoted the consideration of these daies, and medically advanced the same, was the doctrin of Hippocrates; a Physitian of such repute, that he received a testimony from a Christian, that might have been given unto Christ. Qui nec fallere potest nec falli. The first in his book, de Acre, Aquis, et locis. Syderum ortus, etc. That is, we are to observe the rising of Stars, especially the Dog-star, Arcturus, and the setting of the Pleiades or seven Stars. From whence notwithstanding we cannot infer the general efficacy of these Stars, or co-efficacy particular in medications. Probably expressing no more hereby then if he should have plainly said, especial notice we are to take of the hottest time in Summer, of the beginning of Autumn and Winter; for by the rising and setting of those Stars were these times and seasons defined. Diseases commonly determined, by what seasons. And therefore subjoyns this reason, Quoniam his temporibus morbi finiuntur, because at these times diseases have their ends; as Physitians well known, and he elsewhere affirmeth, that seasons determine diseases, beginning in their contraries; as the Spring the diseases of Autumn, and the Summer those of Winter. Now (what is very remarkable) whereas in the some place he adviseth to observe the times of notable mutations, as the Equinoxes, and the Solstices, and to decline Medication ten daies before and after; how precisely soever canicular cautions be considered, this is not observed by Physitians, nor taken notice of by the people. And indeed should we blindly obey the restraints both of Physitians and Astrologers, we should contract the liberty of our prescriptions, and confine the utility of Physick unto a very few daies. For observing the Dog-daies, and as is expressed, some daies before, likewise ten daies before and after the Equinoctial and Solsticial points; by this observation alone are exempted an hundred daies. Whereunto if we add the two Egyptian daies in every month, the interlunary and plenilunary exemptions, the Eclipses of Sun and Moon, conjunctions and oppositions Planetical, the houses of Planets, and the site of the Luminaries under the signs (wherein some would induce a restraint of Purgation or Phlebotomy) there would arise above an hundred more; so that of the whole year the use of Physick would not be secure much above a quarter. Now as we do not strictly observe these daies, so need we not the other; and although consideration be made hereof, yet must we prefer the nearer indications before those which are drawn from the time of the year; or other cælestial relations.