We can immediately see the connection between Ga1-18 and Gb7-18, not only by their looks but also by their numbers (-18).

Ga1-18, we have noted, comes 4 days before a tao glyph which in turn comes 4 days before Ga1-26, a glyph of obvious importance which I have classified as gagana, but which could well be its opposite in meaning:

The 'eyes' in Ga1-26 are both outside and in place, while in Ga1-18 the left mata (from us seen) is inside and cannot be seen. There is a hole where the right mata should have been. 'Viri' at bottom in Ga1-18 shadows while 'viri' in Ga1-26 is open for the incoming light.

Ga1-26 marks day 64 + 27 = 91 counted from winter solstice. The location of the text segment above is spring equinox. Maybe gagana in Ga1-18 refers to the first of 8 dark days before the 'morning light' (spring sun) returns. The hole at right could be representing this 8-day long 'dark' period, alluding to the 8 days when Venus has disappeared before she comes back again as morning star.