(Chalcidian th) may have been used originally; but C (the abbreviation for centum) came into use at an early period. The sign D, = 500, is the half of ↀ.
[2408.] To denote 10,000 the sign for 1000 was doubled: thus, ↂ, written also
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. Another circle was added to denote 100,000: thus, ↈ, written also
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