die obfervationum,habebiturque differentia decUnatio-nis. Ponatur jam, hanc diflferentiam efle 18. minutorum. Fiat itaque: ut ^ ^ adi8.minuta5 ita BC diameter folaris ad quartum j & proveniet numerus minuto-rumin folaridiametro contentorum. Ratioeft,quiadifterentiadecUnationisi8. mi-nutorum…
Optics, Geometrical · Optical instruments
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