Salusbury, Thomas
,
Mathematical collections and translations (Tome I)
,
1667
Text
Text Image
Image
XML
Thumbnail overview
Document information
None
Concordance
Figures
Thumbnails
Page concordance
<
1 - 30
31 - 60
61 - 90
91 - 120
121 - 150
151 - 180
181 - 210
211 - 240
241 - 270
271 - 300
301 - 330
331 - 360
361 - 390
391 - 420
421 - 450
451 - 480
481 - 510
511 - 540
541 - 570
571 - 600
601 - 630
631 - 660
661 - 690
691 - 701
>
Scan
Original
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
<
1 - 30
31 - 60
61 - 90
91 - 120
121 - 150
151 - 180
181 - 210
211 - 240
241 - 270
271 - 300
301 - 330
331 - 360
361 - 390
391 - 420
421 - 450
451 - 480
481 - 510
511 - 540
541 - 570
571 - 600
601 - 630
631 - 660
661 - 690
691 - 701
>
page
|<
<
of 701
>
>|
<
archimedes
>
<
text
>
<
body
>
<
chap
>
<
p
type
="
main
">
<
s
>
<
pb
xlink:href
="
040/01/374.jpg
"
pagenum
="
345[354]
"/>
facility apprehended in the
<
emph
type
="
italics
"/>
Prolomaick
<
emph.end
type
="
italics
"/>
Syſteme.</
s
>
</
p
>
<
p
type
="
main
">
<
s
>SALV. </
s
>
<
s
>I neither ought, nor can deny any thing that
<
emph
type
="
italics
"/>
Sagredus
<
emph.end
type
="
italics
"/>
<
lb
/>
ſhall requeſt: And the delay by me deſired was to no other end,
<
lb
/>
ſave only that I might have time once again to methodize thoſe
<
lb
/>
prefatory points, in my fancy, that ſerve for a large and plain
<
lb
/>
claration of the manner how the forenamed accidents follow, as
<
lb
/>
well in the
<
emph
type
="
italics
"/>
Copernican
<
emph.end
type
="
italics
"/>
poſition, as in the
<
emph
type
="
italics
"/>
Ptolomaick
<
emph.end
type
="
italics
"/>
: nay, with
<
lb
/>
<
arrow.to.target
n
="
marg678
"/>
<
lb
/>
much greater facility and ſimplicity in that than in this. </
s
>
<
s
>Whence
<
lb
/>
one may manifeſtly conceive that Hypotheſis to be as eaſie to be
<
lb
/>
effected by nature, as difficult to be apprehended by the
<
lb
/>
ſtanding: yet nevertheleſſe, I hope by making uſe of another
<
lb
/>
<
arrow.to.target
n
="
marg679
"/>
<
lb
/>
kind of explanation, than that uſed by
<
emph
type
="
italics
"/>
Copernicus,
<
emph.end
type
="
italics
"/>
to render
<
lb
/>
wiſe the apprehending of it ſomewhat leſſe obſcure. </
s
>
<
s
>Which
<
lb
/>
that I may do, I will propoſe certain ſuppoſitions of themſelves
<
lb
/>
known and manifeſt, and they ſhall be theſe that follow.</
s
>
</
p
>
<
p
type
="
margin
">
<
s
>
<
margin.target
id
="
marg678
"/>
<
emph
type
="
italics
"/>
The
<
emph.end
type
="
italics
"/>
<
lb
/>
can
<
emph
type
="
italics
"/>
Syſteme
<
lb
/>
cult to be
<
lb
/>
ſtood, but eaſie to
<
lb
/>
be effected.
<
emph.end
type
="
italics
"/>
</
s
>
</
p
>
<
p
type
="
margin
">
<
s
>
<
margin.target
id
="
marg679
"/>
<
emph
type
="
italics
"/>
Neceſſary
<
lb
/>
poſitions for the
<
lb
/>
better conceiving
<
lb
/>
of the conſequences
<
lb
/>
of the Earths
<
lb
/>
tion.
<
emph.end
type
="
italics
"/>
</
s
>
</
p
>
<
p
type
="
main
">
<
s
>Firſt, I ſuppoſe that the Earth is a ſpherical body, turning
<
lb
/>
round upon its own Axis and Poles, and that each point aſſigned
<
lb
/>
in its ſuperficies, deſcribeth the circumference of a circle,
<
lb
/>
er or leſſer, according as the point aſſigned ſhall be neerer or
<
lb
/>
farther from the Poles: And that of theſe circles the greateſt is
<
lb
/>
that which is deſcribed by a point equidiſtant from the ſaid Poles;
<
lb
/>
and all theſe circles are parallel to each other; and
<
emph
type
="
italics
"/>
Parallels
<
emph.end
type
="
italics
"/>
we
<
lb
/>
will call them.</
s
>
</
p
>
<
p
type
="
main
">
<
s
>Secondly, The Earth being of a Spherical Figure, and of an
<
lb
/>
pacous ſubſtance, it is continually illuminated by the Sun,
<
lb
/>
ding to the half of its ſurface, the other half remaining obſcure,
<
lb
/>
and the boundary that diſtinguiſheth the illuminated part from
<
lb
/>
the dark being a grand circle, we will call that circle the
<
emph
type
="
italics
"/>
<
lb
/>
nator of the light.
<
emph.end
type
="
italics
"/>
</
s
>
</
p
>
<
p
type
="
main
">
<
s
>Thirdly, If the Circle that is terminator of the light ſhould
<
lb
/>
paſſe by the Poles of the Earth, it would cut (being a grand
<
lb
/>
and principal circle) all the parallels into equal parts; but not
<
lb
/>
paſſing by the Poles, it would cut them all in parts unequal,
<
lb
/>
cept only the circle in the middle, which, as being a grand circle
<
lb
/>
will be cut into equal parts.</
s
>
</
p
>
<
p
type
="
main
">
<
s
>Fourthly, The Earth turning round upon its own Poles, the
<
lb
/>
quantities of dayes and nights are termined by the arches of the
<
lb
/>
Parallels, interſected by the circle, that is, the terminator of the
<
lb
/>
light, and the arch that is ſcituate in the illuminated Hemiſphere
<
lb
/>
preſcribeth the length of the day, and the remainer is the
<
lb
/>
tity of the night.</
s
>
</
p
>
<
p
type
="
main
">
<
s
>Theſe things being preſuppoſed, for the more clear
<
lb
/>
<
arrow.to.target
n
="
marg680
"/>
<
lb
/>
ſtanding of that which remaines to be ſaid, we will lay it down
<
lb
/>
in a Figure. </
s
>
<
s
>And firſt, we will draw the circumference of a
<
lb
/>
circle, that ſhall repreſent unto us that of the grand Orb </
s
>
</
p
>
</
chap
>
</
body
>
</
text
>
</
archimedes
>