ON THE MODULAR FIGURE AND FORD-SPHERES

In 1 we study Figure 1 for variable h. In 2 and 3 this is combined wit h Ford-circles (Figure 2) and the choice h = 0 (Figure 3). In 4 a limi t is evaluated. In 5 we treat Figure 5 (''Ford-circles inside the unit -circle'') and a technical application. In 6 contains various modular figures (Figures 7, 8, 9). 7 treats synchronous rotation of Figure 1 a nd going from R-2 to R-3; the rotating upper half-plane of C correspon ds then to the unit-sphere. In 8 a sphere-packing on Cis introduced. F inally in 9 a sphere-packing inside the unit-sphere arises.