ear day. We can see that some of the Z10's occurred in post month 9 of the previous year.</p>
    
<p>The lunation fraction of a solar term increased by <span class="nowrap">7/19</span> (mod 1) every year and it repeated with a cycle of 19 years. This was not the case for the dates of solar terms in the Chinese calendar. Take the winter solstice (Z11) as an example. In example 1 in Section 4, we find that the lunation fraction of Z11 in <span class="nowrap">N<sub>-130</sub></span> was <span class="nowrap">1