Observe that we can bisect a day into two ⚀clock periods (semi·days), each 6 ⚀dwells long (equivalent to 60_z ⚀breathers, or 600_z ⚀trices, or 10_z=12_d hours, or 500_z=720_d minutes). But where should we make the partition? The modern Western convention, of course, is to divide the day at noon and midnight, yielding the familiar Ante Meridiem (A.M.) and Post Meridiem (P.M.) ⚀clock periods. These are Latin for “Before Mid-Day” and “After Mid-Day”.

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Hence the ⚀clock periods are combinations of two adjacent ⚀phases each:

We can divide each ⚀phase into 3 ⚀dwells, and assign them names: Early, Mid, and Late:

In a Primel world, people would likely tell time in terms of the ⚀trice count. Since the ⚀trice is 5/6 of a minute, this gives accuracy to the minute and better, using only three dozenal digits. Conventional 12_d-hour clock time requires four digits plus an indicator of the current ⚀clock period, A.M. or P.M. TGM time in ⚀lapses does better in that the hour is encoded in a single digit and the top digit encodes the  ⚀clock period (0=A.M., 1=P.M.). However, one more digit only gives accuracy down to the nearest 5-minute (6-⚀trice) ⚀block. To get at least minute accuracy in TGM requires 4 digits. But because the ⚀lapse is half the size of the ⚀trice, and only 25_d seconds long, this provides too much accuracy, at the expense of taking up an additional digit. Bottom line, the Primel scheme is the most compact.

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