6 + 7 = 13 and 13 * 20 = 260. Time is measured by Moon, she has day number 20 (and the other key numbers of the calendar). But Mars is important because there seems to be a quarter of growth (7 * 13 = 91 days) depending on him.

Mercury is a liquid and represents the opposite pole, the sudden collapse of the fertile 'tree' which has grown during the reign of Mars, while old Jupiter comes at the end of the season of light. He must be responsible enough to end in order to realease his vital spirit (manu rere) needed for next generation.

Sun as a little newborn child has number 5 (rima, fire, fingers). Before that there is darkness -  the kind of complete darkness in which a new fire must be alighted, a new life created. That is Saturn's day. Number 4 is the smallest square number, and from this fact, I guess, originates the idea of Saturn as a cube (where the sides are 6 squares):

(Hamlet's Mill)

We should notice that the square of 'fire', 25, belongs to Saturn in my chart.