He proved geometrically in his Horologium Oscillatorium, originally published in , that the curve was a cycloid. On a cycloid whose axis is erected on the perpendicular and whose vertex is located at the bottom, the times of descent, in which a body arrives at the lowest point at the vertex after having departed from any. Figure 3 CD spectra (upper curves) and UV–Vis spectra (bottom curves) of original GNRs (black curves) and L-CYS-GNR [email protected] core–shell nanostructures fabricated with different Cit concentrations. The AR of GNRs is (a) ~ and (b) ~ The numbers in the labels correspond to the Cit concentration in the. 21 Mar So how do you figure out the orientation of the curves? Meaning, how do you figure out which curves is on the top and which is on the bottom, or which curve is on the right and which is on the left? The good news is that figuring out the orientation of the curves is actually not too difficult. All you need to do is.