A grid oriented to the East with 6 engraved hour lines and three curves indicated, with the help of the shadow trace from the horizontal (perpendicular to the grid) gnomon tip, the 5 unequal (depending on the season) day hours after the sunrise (1st, 2nd, 3rd, 4th and 5th). The horizontal hour line at the height of the gnomon indicated the sunrise. The higher curve indicated the course of the Sun’s shadow at the winter solstice, the lower at the summer solstice and the middle straight line at the equinoxes.