Beginning of the Count of Time
Event Type: Cultural/Social
In seven hours the glory of each tree waxed to full and waned again to naught; and each awoke once more to life an hour before the other ceased to shine. Thus in Valinor twice every day there came a gentle hour of softer light when both trees were faint and their gold and silver beams were mingled. Telperion was the elder of the trees and came first to full stature and to bloom; and that first hour in which he shone, the white glimmer of a silver dawn, the Valar reckoned not into the tale of hours, but named it the Opening Hour, and counted from it the ages of their reign in Valinor. Therefore at the sixth hour of the First Day, and of all the joyful days thereafter, until the Darkening of Valinor, Telperion ceased his time of flower; and at the twelfth hour Laurelin her blossoming. And each day of the Valar in Aman contained twelve hours, and ended with the second mingling of the lights, in which Laurelin was waning but Telperion was waxing.... Thus began the Days of the Bliss of Valinor; and thus began also the Count of Time.
The Silmarillion, Quenta Silmarillion, Ch 1, Of The Beginning of Days
For the Trees waxed to full bloom and light, and waned again, unceasingly, without change of speed or fullness. Telperion came first to flower, and a little ere he ceased to shine Laurelin began to bud; and again ere Laurelin had grown dim Telperion awoke once more. Therefore the Valar took the time of the flowering, first of Telperion and then of Laurelin, to be for them a Day in Valinor; and the time when each Tree was flowering alone they divided into five hours, each equal to the time of the mingling of their lights, twice in each Day. There were thus twelve such hours in every Day of the Valar; and one thousand of those Days was held to be a Year, for then the Trees would put forth a new branch and their stature would increase.
Morgoth's Ring, HoME Vol 10, Part 2, The Annals of Aman
Elena Tiriel 29Nov07