1
tions; the one is its riſing and falling alternately towards the
one and other extremity; the other is its moving and running, to
ſo ſpeak, Horizontally forwards and backwards. Which two
ferent motions differently reſide in divers parts of the Water:
for its extream parts are thoſe which moſt eminently riſe and fall;
thoſe in the middle never abſolutely moving upwards and
wards, of the reſt ſucceſſively thoſe that are neereſt to the
treams riſe and fall proportionally more than the remote: but on
the contrary, touching the other progreſſive motion forwards
and backwards, the middle parts move notably, going and
turning, and the waters that are in the extream parts gain no
ground at all; ſave onely in caſe that in their riſing they
flow their banks, and break forth of their firſt channel and
ceptacle; but where there is the obſtacle of banks to keep them
in, they onely riſe and fall; which yet hindereth not the waters
in the middle from fluctuating to and again; which likewiſe
the other parts do in proportion, undulating more or leſſe,
according as they are neerer or more remote from the
tions; the one is its riſing and falling alternately towards the
one and other extremity; the other is its moving and running, to
ſo ſpeak, Horizontally forwards and backwards. Which two
ferent motions differently reſide in divers parts of the Water:
for its extream parts are thoſe which moſt eminently riſe and fall;
thoſe in the middle never abſolutely moving upwards and
wards, of the reſt ſucceſſively thoſe that are neereſt to the
treams riſe and fall proportionally more than the remote: but on
the contrary, touching the other progreſſive motion forwards
and backwards, the middle parts move notably, going and
turning, and the waters that are in the extream parts gain no
ground at all; ſave onely in caſe that in their riſing they
flow their banks, and break forth of their firſt channel and
ceptacle; but where there is the obſtacle of banks to keep them
in, they onely riſe and fall; which yet hindereth not the waters
in the middle from fluctuating to and again; which likewiſe
the other parts do in proportion, undulating more or leſſe,
according as they are neerer or more remote from the
Water riſeth &
falleth in the
tream parts of the
Veſſel, and runneth
to and fro in the
midst.
falleth in the
tream parts of the
Veſſel, and runneth
to and fro in the
midst.
An accident of
the Earths motions
impoſſible to be
duced to practice
by art.
the Earths motions
impoſſible to be
duced to practice
by art.
The fifth particular accident ought the more attentively to be
conſidered, in that it is impoſſible to repreſent the effect
of by an experiment or example; and the accident is this. In
the veſſels by us framed with art, and moved, as the
named Bark, one while more, and another while leſſe ſwiftly,
the acceleration and retardation is imparted in the ſame manner
to all the veſſel, and to every part of it; ſo that whilſt v. g. the
Bark forbeareth to move, the parts precedent retard no more
than the ſubſequent, but all equally partake of the ſame
tardment; and the ſelf-ſame holds true of the acceleration,
namely, that conferring on the Bark a new cauſe of
ter velocity, the Prow and Poop both accelerate in one and
the ſame manner. But in huge great veſſels, ſuch as are the very
long bottomes of Seas, albeit they alſo are no other than
tain cavities made in the ſolidity of the Terreſtrial Globe,
it alwayes admirably happeneth, that their extreams do not
unitedly equall, and at the ſame moments of time increaſe
and diminiſh their motion, but it happeneth that when one of its
extreames hath, by vertue of the commixtion of the two
Motions, Diurnal, and Annual, greatly retarded its velocity,
the other extream is animated with an extream ſwift motion.
Which for the better underſtanding of it we will explain,
ſuming a Scheme like to the former; in which if we do but
poſe a tract of Sea to be long, v. g. a fourth part, as is the arch
B C [in Fig. 2.] becauſe the parts B are, as hath been already
declared, very ſwift in motion, by reaſon of the union of the
two motions diurnal and annual, towards one and the ſame way,
conſidered, in that it is impoſſible to repreſent the effect
of by an experiment or example; and the accident is this. In
the veſſels by us framed with art, and moved, as the
named Bark, one while more, and another while leſſe ſwiftly,
the acceleration and retardation is imparted in the ſame manner
to all the veſſel, and to every part of it; ſo that whilſt v. g. the
Bark forbeareth to move, the parts precedent retard no more
than the ſubſequent, but all equally partake of the ſame
tardment; and the ſelf-ſame holds true of the acceleration,
namely, that conferring on the Bark a new cauſe of
ter velocity, the Prow and Poop both accelerate in one and
the ſame manner. But in huge great veſſels, ſuch as are the very
long bottomes of Seas, albeit they alſo are no other than
tain cavities made in the ſolidity of the Terreſtrial Globe,
it alwayes admirably happeneth, that their extreams do not
unitedly equall, and at the ſame moments of time increaſe
and diminiſh their motion, but it happeneth that when one of its
extreames hath, by vertue of the commixtion of the two
Motions, Diurnal, and Annual, greatly retarded its velocity,
the other extream is animated with an extream ſwift motion.
Which for the better underſtanding of it we will explain,
ſuming a Scheme like to the former; in which if we do but
poſe a tract of Sea to be long, v. g. a fourth part, as is the arch
B C [in Fig. 2.] becauſe the parts B are, as hath been already
declared, very ſwift in motion, by reaſon of the union of the
two motions diurnal and annual, towards one and the ſame way,
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