+------+--------------+--------------+--------------+ | | Sun in | Sun in | Sun in | | Lat. | ♈ ♎ | ♋ | ♑ | +------+--------------+--------------+--------------+ | 0 | 20000 | 18341 | 18341 | | 10 | 19696 | 20290 | 15834 | | 20 | 18794 | 21737 | 13166 | | 30 | 17321 | 22651 | 10124 | | 40 | 15321 | 23048 | 6944 | +------+--------------+--------------+--------------+ | 50 | 12855 | 22991 | 3798 | | 60 | 10000 | 22773 | 1075 | | 70 | 6840 | 23543 | 000 | | 80 | 3473 | 24673 | 000 | | 90 | 0000 | 25055 | 000 | +------+--------------+--------------+--------------+ Those that desire more of the Nature of this Problem, as to the Geometry thereof, would do well to compare the XIII. _Prop. Cap. V._ of the Learned Treatise, _De Calculo Centri Gravitatis_, by the Reverend Dr. _Wallis_, Published _Anno 1670_. From this Rule there follow several Corollaries worth Note: As I. That the Æquinoctial Heat, when the Sun comes Vertical, is as twice the Square of _Radius_, which may be proposed as a Standard to compare with, in all other Cases. II. That under the Æquinoctial, the Heat is as the _Sine_ of the Sun's Declination. III. That in the Frigid Zones when the Sun sets not, the Heat is as the Circumference of a Circle into the _Sine_ of the Altitude at 6. And consequently, that in the same Latitude these Aggregates of Warmth, are as the _Sines_ of the Sun's Declinations; and in the same Declination of _Sol_, they are as the _Sines_ of the Latitude, and generally they are as the _Sines_ of the Latitude into the _Sines_ of Declination. IV. That the Æquinoctial Days Heat is every where as the Co-sine of the Latitude. V. In all places where the Sun sets, the difference between the Summer and Winter Heats, when the Declinations are contrary, is equal to a Circle into the _Sine_ of the Altitude at six in the Summer Parallel, and consequently those differences are as the _Sines_ of Latitude into, or multiplied by the _Sines_ of Declination. VI. From the Table I have added, it appears, that the Tropical Sun under the Æquinoctial, has, of all others, the least Force. Under the Pole it is greater than any other Days Heat whatsoever, being to that of the Æquinoctial as 5 to 4. From the Table and these Corollaries may a general _Idea_ be conceived of the Sum of all the Actions of the Sun in the whole Year, and that part of the Heat that arises simply from the Presence of the Sun be brought to a Geometrical Certainty: And if the like could be performed for Cold; which is something else than the bare Absence of the Sun, as appears by many Instances, we might hope to bring what relates to this part of _Meteorology_ to a perfect Theory.