654638GNOMONICES
ſcriptus circulus in 24.
horas ęquales diuidatur, quæ rurſus, ſi placet, in ſemihoras, &
in quadrã-
tes horarum ſubdiuidantur. Rectæ enim ductæ per bina quęuis puncta æqualiter à punctis L, O,
423[Figure 423]11102220333044405550
remota dabunt 12.
horas à meridie, &
12.
à med.
noc.
quarum M A, ſextam horam dabit, ante-
meridianę vero horæ à recta E O, verſus F L, & pomeridianæ à recta F L, verſus E O, numeran-
tur. Term inabuntur autem hæ lineæ horarum, in ſuperiore quidem parte, in circunferentia cir-
culi ex M, ad interuallum M A, deſcripti, in inferiori autem in linea ipſi L O, parallela tanto ſal-
tem interuallo diſtante à recta L O, quanta eſt portio rectæ A I, vel A K, inter A, & rectam F L.
tes horarum ſubdiuidantur. Rectæ enim ductæ per bina quęuis puncta æqualiter à punctis L, O,
meridianę vero horæ à recta E O, verſus F L, & pomeridianæ à recta F L, verſus E O, numeran-
tur. Term inabuntur autem hæ lineæ horarum, in ſuperiore quidem parte, in circunferentia cir-
culi ex M, ad interuallum M A, deſcripti, in inferiori autem in linea ipſi L O, parallela tanto ſal-
tem interuallo diſtante à recta L O, quanta eſt portio rectæ A I, vel A K, inter A, & rectam F L.
RVRSVS fabricandum erit brachiolum ex dura aliqua, &
ſolida materia, conſtans tribus
volubilibus ſegmentis Q R, R S, S T, quæ in longum extenſa longitudinem efficiant rectæ G A,
æqualem. Huius brachioli extremum punctum Q, figendum eſt in puncto G, ita vt alterum extre
mum T, liberæ per omnia loca trianguli A, E F, diſcurrere poſſit, & in quocunque loco firmari,
volubilibus ſegmentis Q R, R S, S T, quæ in longum extenſa longitudinem efficiant rectæ G A,
æqualem. Huius brachioli extremum punctum Q, figendum eſt in puncto G, ita vt alterum extre
mum T, liberæ per omnia loca trianguli A, E F, diſcurrere poſſit, & in quocunque loco firmari,
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