Artificial_
dayes as contradistinguished to nights, yet that the _Natural_ Days,
reckoning from noon to noon, are all _equal_: But _Astronomers_ know well,
that even these dayes are _unequal_.

For, this _Natural_ Day is measured _not onely_ by one intire conversion of
the _AEquinoctial_, or 24. _AEquinoctial_ hours, (which is indeed taken to be
performed in equal times,) _but_ increases by so much, as answers to that
part of the _Sun's_ (or _Earths_,) Annual motion as is performed in that
time. For, when that part of the _AEquinoctial_, which (with the _Sun_) was
the _Meridian_ yesterday at noon, is come thither again to day, it is not
yet _Noon_ (because the Sun is not now at the place where yesterday he was,
but is gone forward about one degree, more or less) but we must stay till
that place, where the _Sun_ now is, comes to the _Meridian_ before it be
now _Noon_.

Now this Additament (above the 24 _AEquinoctial_ hours, or intire conversion
of the _AEquinoctial_) is upon a double account {278} unequal. _First_,
because the Sun, by reason of its _Apogaeum_ and _Perigaeum_, doth not at all
times of the year dispatch in one day an equal Arch of the _Ecliptick_; but
greater Arches neer the _Perigaeum_, which is about the middle of
_December_; and lesser neer the _Apogaeum_, which is about the middle of
_June_: As will appear sufficiently by the _Tables_ of the Sun's Annual
motion. _Secondly_, though the Sun should in the _Ecliptick_ move alwaies
at the same rate; yet equal Arches of the _Ecliptick_ do not in all parts
of the _Zodiack_ answer to equal Arches of the _AEquinoctial_, by which we
are to estimate time: Because some parts of it, as about the two
_Solsticial_ Points, lie nearer to a _parallel_ position to the
_AEquinoctial_, than others, as those about the two _AEquinoctial_ points,
where the _Ecliptick_ and _AEquinoctial_ do intersect; whereupon an Arch of
the _Ecliptick_, neer the _Solsticial_ points answers to a greater Arch of
the _AEquinoctial_, than an Arch equal thereunto neer the _AEquinoctial_
points: As doth sufficiently appear by the _Tables_ of the Suns _right
Ascension_.

According to the _first_ of these causes, we should have the longest
_natural_ daies in _December_, and the shortest in _June_, which if it did
operate alone, would give us at those times two _Annual_ High-waters.

According to the _second_ cause, if operating singly, we should have the
longest daies at the two Solstices in _Jun