Possibly what is rising is vapour, because sun is heating up the earth in spring. Beyond midsummer water is coming down in rain form, and even a little child understands that the rain water must first have been uplifted into the sky.

The normal form of pu glyphs suggests two 'water pools', but there is a variant without such:

pu		Ha7-38

If sun in spring is drawing up all water from the pools on the surface of the earth, then the variant without 'holes' naturally would tend to appear before midsummer (when there is no more water to 'suck up'). And at - or immediately after - midsummer there would be a tendency for (waterfilled) 'holes' to once again appear on earth and in the rongorongo texts. St John the Baptist is located at midsummer.

Fingers (and toes) were fire symbols in Polynesia (cfr how Maui played tricks on his ancestress Mahuika), and in the rongorongo system of writing fingers may have been used also to indicate water, possibly in such glyphs as these:

Db1-103	Pa2-42	Ab7-59
Da3-108	Na4-101	Aa1-74

This explanation of the sign at right in Ha7-38 (meaning that the time of water reversal has been reached because the 'pools' on earth are dried up) carries implicitly with it the assumption that it is a variant of henua which is used in the pu glyphs.

In Hawaii one of the names of Saturn was Dripping Water, and in Saturday we can first see droplets in Hb9-54 and then, in Hb9-55, the resulting waterfilled holes:

Hb9-51	Hb9-52	Hb9-53	Hb9-54
Hb9-55	Hb9-56	Hb9-57	Hb9-58

(Henua in Hb9-57 is a variant of the 'midnight henua', and the preceding Rei indicates a new 'season' is beginning, a season which we ought to identify as next week. Saturday is the day both of ending and a new beginning. From the water rises a new 'earth'.)

Furthermore, the explanation of the sign at right in Ha7-38 also 'casts light' on another phenomenon, viz. how to understand the name Ohiro for the first night when the new moon is visible.

Hiro 1. A deity invoked when praying for rain (meaning uncertain). 2. To twine tree fibres (hauhau, mahute) into strings or ropes. Vanaga. To spin, to twist. P Mgv.: hiro, iro, to make a cord or line in the native manner by twisting on the thigh. Mq.: fió, hió, to spin, to twist, to twine. Ta.: hiro, to twist. This differs essentially from the in-and-out movement involved in hiri 2, for here the movement is that of rolling on the axis of length, the result is that of spinning. Starting with the coir fiber, the first operation is to roll (hiro) by the palm of the hand upon the thigh, which lies coveniently exposed in the crosslegged sedentary posture, two or three threads into a cord; next to plait (hiri) three or other odd number of such cords into sennit. Hirohiro, to mix, to blend, to dissolve, to infuse, to inject, to season, to streak with several colors; hirohiro ei paatai, to salt. Hirohiroa, to mingle; hirohiroa ei vai, diluted with water. Churchill. Ta.: Hiro, to exaggerate. Ha.: hilohilo, to lengthen a speech by mentioning little circumstances, to make nice oratorial language. Churchill. Ohirohiro Waterspout (more exactly pú ohirohiro), a column of water which rises spinning on itself. Vanaga.

A fresh new moon is rising from having bathed in the Living Water of Tane:

... when the new moon appeared women assembled and bewailed those who had died since the last one, uttering the following lament: 'Alas! O moon! Thou has returned to life, but our departed beloved ones have not. Thou has bathed in the waiora a Tane, and had thy life renewed, but there is no fount to restore life to our departed ones. Alas'...

Moon is rising by some force similar to a waterspout (ohirohiro). The heat of Tane is the cause. Boiling will make the steam rise, flames always rise, the force of rising is heat. Cooling in the night will cause water to come down and form dew on the ground. At full moon the process of rising is completed, the name Omotohi ('End-of-Sucking') is in complete agreement.

I.e., full moon and midsummer are structurally related - they are points of turning around from waxing to waning, from 'sucking' to 'spewing':

Cb14-17	Aa6-66	Ca3-7	Nb2-112