COROLLARIE XIV.
* Arteſia.
In the Grand Rivers, which fall into the Sea, as here in Italy
Po, Adige,^{*} and Arno, which are armed with Banks againſt their
excreſcencies, its obſerved that far from the Sea, they need
Banks of a notable height; which height goeth afterwards by
degrees diminiſhing, the more it approacheth to the Sea-coaſts:
in ſuch ſort, that the Po, diſtant from the Sea about fifty or ſixty
miles at Ferara, ſhall have Banks that be above twenty feet
higher than the ordinary Water marks; but ten or twelve miles
from the Sea, the Banks are not twelve feet higher than the ſaid
ordinary Water-marks, though the breadth of the River be the
ſame, ſo that the excreſcence of the ſame Innundation happens
to be far greater in meaſure remote from the Sea, then near; and
yet it ſhould ſeem, that the ſame quantity of Water paſſing by
every piace, the River ſhould need to have the ſame altitude of
Banks in all places: But we by our Principles and fundamentals
may be able to render the reaſon of that effect, and ſay; That
that exceſſe of quantity of Water, above the ordinary Water,
goeth alwaies acquiring greater velocity; the nearer it approach
eth the Sea, and therefore decreaſeth in meaſure, and conſequenly
in height. And this perhaps might have been the cauſe in great
part, why the Tyber in the Innundation Anno 1578. iſſued not
forth of its Channel below Rome towards the Sea.
Po, Adige,^{*} and Arno, which are armed with Banks againſt their
excreſcencies, its obſerved that far from the Sea, they need
Banks of a notable height; which height goeth afterwards by
degrees diminiſhing, the more it approacheth to the Sea-coaſts:
in ſuch ſort, that the Po, diſtant from the Sea about fifty or ſixty
miles at Ferara, ſhall have Banks that be above twenty feet
higher than the ordinary Water marks; but ten or twelve miles
from the Sea, the Banks are not twelve feet higher than the ſaid
ordinary Water-marks, though the breadth of the River be the
ſame, ſo that the excreſcence of the ſame Innundation happens
to be far greater in meaſure remote from the Sea, then near; and
yet it ſhould ſeem, that the ſame quantity of Water paſſing by
every piace, the River ſhould need to have the ſame altitude of
Banks in all places: But we by our Principles and fundamentals
may be able to render the reaſon of that effect, and ſay; That
that exceſſe of quantity of Water, above the ordinary Water,
goeth alwaies acquiring greater velocity; the nearer it approach
eth the Sea, and therefore decreaſeth in meaſure, and conſequenly
in height. And this perhaps might have been the cauſe in great
part, why the Tyber in the Innundation Anno 1578. iſſued not
forth of its Channel below Rome towards the Sea.
COROLLARIE XV.
From the ſame Doctrine may be rendred a moſt manifeſt rea
ſon why the falling Waters go leſſening in their deſcent, ſo
that the ſame falling Water, meaſured at the beginning of
its fall, is greater, and bigger, and afterwards by degrees leſſeneth
in meaſure the more it is remote from the beginning of the fall.
Which dependeth on no other, than on the acquiſition, which
it ſucceſſively makes of greater velocity; it being a moſt fami
liar concluſion among Philoſophers, that grave bodies falling,
the more they remove from the beginning of their motion, the
more they acquire of ſwiftneſſe; and therefore the Water, as a
grave body, falling, gradually velocitates, and therefore de
creaſeth in meaſure, and leſſeneth.
ſon why the falling Waters go leſſening in their deſcent, ſo
that the ſame falling Water, meaſured at the beginning of
its fall, is greater, and bigger, and afterwards by degrees leſſeneth
in meaſure the more it is remote from the beginning of the fall.
Which dependeth on no other, than on the acquiſition, which
it ſucceſſively makes of greater velocity; it being a moſt fami
liar concluſion among Philoſophers, that grave bodies falling,
the more they remove from the beginning of their motion, the
more they acquire of ſwiftneſſe; and therefore the Water, as a
grave body, falling, gradually velocitates, and therefore de
creaſeth in meaſure, and leſſeneth.
COROLLARIE XVI.
And on the contrary, the ſpirtings of a Fountain of Water,
which ſpring on high, work a contrary effect; namely
which ſpring on high, work a contrary effect; namely