Serenitatem_ dabit.

That is,

IF the rising Sun be incompassed with an Iris, or Circle of white
Clouds, and they equally fly away, this is a Sign of fair Weather.

THERE is another _English_ Proverb worth remembering.

In the Decay of the Moon,
A cloudy Morning bodes a fair Afternoon.

IV.

_Large like Rocks._----Great Showers.

IN the old Almanacks we have this Sign of the Weather thus expressed.

When Clouds appear like Rocks and Towers,
The Earth's refresh'd by frequent Showers.

THE Reason of this seems to be, that the watery Vapours are then
condensed, or condensing, which gives them this rough and ragged
Appearance, and as soon as the thin Films that retain the Water are
broke by this Pressure, these heavy Clouds descend in Rain.

THESE Observations, as well as some that follow, are agreeable to all
Climates, which is the Reason that they appear in so many different
Authors, and have been taken notice of in so many Ages. This however
does not at all diminish the Credit, or the Merit of our Shepherd's
Observations, who certainly drew them not from Books, but from his own
Experience, and therefore their agreeing so well with the Rules of
other great Masters, ought to establish his Authority in such Cases as
are not supported by alike concurrence from ancient or modern Writers,
the Testimony of Nature is always sufficient Evidence.

V.

_If small Clouds increase_----Much Rain.

THIS and the following Observation cannot well be understood, without
giving some Account of Clouds in general. The Atmosphere is supposed to
extend itself about five Miles round this Globe of Earth, and within
that Space move all kind of Vapours exhaled by the Sun's Force, or
protruded by the subterraneous Heat. The ascending of these Vapours
into the Air, depends upon many things, and therefore as different as
its Causes; for instance, their ascent depends in the first place on
the degree of Heat with which they are drawn up or forced out; next
upon the Lightness of the Vapours themselves; thirdly, on the Density
or Rarity of the Air through which they pass; and lastly, on the Force
and Direction of the Winds, which they encounter in their Passage.

ACCORDING to the Nature of these Vapours, and the Circumstance
attending their Passage, they appear to us differently below. For if
they be extremely subtile they mount very high, and there, according to
the Sentiment of Sir _I