This was a short work containing an estimation of the angle of depression of the sun at the beginning of the morning twilight and at the end of the evening twilight, and an attempt to calculate on the basis of this and other data the height of the atmospheric moisture responsible for the refraction of the sun's rays.
To je bilo kratko djelo koje je sadržavalo procjenu kuta depresije Sunca na početku zore i pri kraju sutona, te pokušaj izračuna na temelju toga i ostalih podataka visine atmosferske vlage odgovorne za refrakciju Sunčevih zraka.