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Perfpeétiv~
P E.R S P
'E
C T IV
JE
LIBER SECUN,DUS.
Ichnqgraphia Projeéta.
le
t:ber,
fla~t
&
feq11entes totUJ
pr~élicUJ
ef¡'
c~mm1tnefq11e
pr11xes..fx pr11f,1p:.
,
pojitu propojittombru demon.flr11t. f2.!!_ta autcm 11t Jam[upra monui, eo {ere ordine
procedit perj}eEliva fcienti11, r¡uo Archite{/onica,r¡tt&
a
fandamenta incipiJ; pri–
mo omnem tchnogr11phiam Geometricam
,
in tabe!U perJJeaiv'e delineal'e dolebo,
qr111 methodU1 fao!lima videtM, lícet in aliqrub¡u cajib1H al1quanto longior vi-
de11tttr. Totru igitur hic liber circaplana hmzontalia ocwpabitttr,pr11cip11e vero illud
cui
tabe//,,
i¡¡fijlit, !icet eti11m method11m oper11ndi, in 11li11 pl11nio ipji para!!elio ,Jive infra, jivefi1pra p1m–
llttm principale ppjitu jim indicattmu. Clari:fimttm alltem ejl,plana horizoJ'/talia infra prmElrtm'
viSJ2s pojittrfaciem fuperiorem nobú exhibere, q1111 ver'ii fr1pra p11nélrtm principale
,
&
confequen–
terfrpra ocul11m, eflendere inferiorem faciem. lndtc11bo etiam omnes praxes plani horizont11lit,
pl11nfr verticalibUJ, immo
&
ommb& ad tabellfm reftis applícari pojfe.
Pt
ver'¡¡ praxes
tjl
"-
'11dh11c 1miverfalioru reddantllf, not11nd11m
ejl
non tant11r» corpora, q1111.
vert
&
realiter eidem horizomali plano infifltmt,
rni
tabella inwmbit, h11bentqr1e in eo, alíqrwn
ut ita dic11m plantam; fed ea etiam qu11 ab eo longius drjlant
,
aut in aere fum pend1fl11
,
poffe
11/ir¡r1111nfi[/itiam h11bere ptanlttm, ita
fil
cog,iffnt(ir demitti
a
Jingulis somm ang11lis 11liq1111 per–
vendimtarcs,1tfq11e ad planum horizontale. rtJi Jint corp11< fa!id11m •ABC
D,
pojfimt cugitari ex
D
Ji11g11lis 11ng1tlis ABCDEF, demitti linelfl perpendirnlares AH,
E K,
EJ,BO, &c. qru inplanofrebjcélo jig111am formab11nt AH
JO,
q11lfl
mt
bajis corporiJ
AC,
in eo jitu coltocati.
C
Si corporis lchnographia pa11lo
~1ficilior
faerit,
&
íntricata,
ne~
.
cefferi11m erit, e11m prius Geometrice defcribere, cµm omnib11&
{iús
di–
mmfionib11s, pro111 jimt in
fe,
n,ut/11 habitJ ratimeperj}eEliv11. De–
inde h11c planta, bajis,
fau
lchnographia Geometrica, degradabitttr,
feu in tabellam projici&tllr. Ratio h11j11& rei
ejl,
quod 1d wjtú im11g,o
req11irit1tr mente tenend111n ejl, ji enim non probe cognit11m jit, im–
pofobile
ejl,
11t ej11s imago frmedat.
~ando
1111tem ichnographia plu–
ftmtU fine&,
&
vari~
in1ric11ta continet, difjictie
ejl,
ul
meme
te–
neat11r.
In
faciliorib11S fguris op1ts flon erit Tchnographiam GeometricAm
prir}s delineare. Determi11and11rtamen
ejl
/oms,rei exhibend11. rer6i
:!,
1
•ttia,non frefjiciet proponere defiribe?!drim q11adr11t11m in plano
horizont~li
;
(ed
prlflterea
,
áe~
termi11a11d11s
,efl
lom; ej11s, an ad dex.teram, an adJinjllram, ¡1n m11gnr1rn, an parvum, an mul–
tttm diflans
a
tabella, an pamm; mm enim commrmtter ob1eél11m frepponatflr
eJfe
pefl tabell11J11,
de~et
determim1ri 11n dij?ttum, an propinq1111m jit,{eri 11tmm m11!t1lm intr11- profimditatem tabel–
l.e
ingredi11t11r. ' Deter;ninatllS item
efl.
/oms fPe{/atoris, qttodfiiffcienter
er11jl~t11r,
not(ltO
~am
punilopmmpatt, qriamp1111llts dijlantí.f.
e
.etera 1111/em 1tfas docebi'f.
illilllllllllllllll!llll·1llllll!lll!1J1Joo·1illlliillll1lllllil1J1J1lll!lí'i!1.!111!1
D
e
E
SU P P O S I T 1 O
l.
r=:::--.....:;._---;;;_-----_::_
l
'
Problema.
Q5adrat11m dírtélt oppofi111m
defaribtrt.
Sit quádratum cujus lams AB defcribendum Ad
runétnm principale
C
ducanttir radii
A C, BC,
tte1n
•d punéh
dillamire D
&
E,
ducantur
diago-
·
.B
nales AE BD,fecantes radios in
pm1lHs
F,G.
Pll~
catur linea FG, dico faétum elfc
quod
imperabamr.
.
Demg11fua