The park is pretty great! There are waterspout slides and fountains to run through and pools to swim in and a river that may be traversed in flotation devices and a lake with a variety of borrowable boats. Aurin likes the fountains best and Finnah prefers the slides.
Avar keeps them all in sight, but wisely conserves energy by not going up and down every single line with them. Mial is still a tiny whirlwind even without his potion.
She invents a few spells. First some unexciting variations on cutting or reducing an object's connection to down magic - out of the bowl of oranges she uses as test subjects, she ends up with several that can be kept in the air with the occasional light tap, two that can be sent whizzing across the room with a similar amount of force, and one that bounces crazily from floor to ceiling to counter to wall to wall to floor again until Koridaar cancels the effect and intercepts its last dive with a plate. Splat.
Mial gets to play with the surviving airborne oranges while Koridaar pursues more esoteric possibilities. Interfering with the connection at the source - light objects are less affected by down magic because they are light, so how does one go about making something actually lighter?
None of this batch of oranges survive their contributions to wizarding research. Making objects actually lighter, as opposed to just masking their weight on various levels, seems to be very bad for the objects.
To be thorough, she tests all the orange-safe ones on lizards she finds outside before writing Ehail back. This results in some very confused but otherwise unharmed lizards. She writes out all the spells verified in this way, adding that she doesn't hold out much hope but it seems worthwhile to test them just in case, then gives a briefer list of the various ideas that didn't make it through fruit-based testing. It is her emphatic recommendation that anyone who wants to pursue the make-it-actually-lighter idea should wait until they find a version that doesn't violently destroy a gently handled orange before proceeding to testing on anything with a brain.
She reminds Ehail that she and her family are available whenever Ehail comes up with an analysis she wants to try.
Mial happens to see this letter, and comes up with a multitude of designs for possible wing extensions. Koridaar takes him to the bottom of the world and lets him try them out, in combination with the various safe lightening spells. He has lots of fun, but of course can do nothing to verify whether any of this would affect esu; he hardly goes two waking angles without birding around. Koridaar nevertheless records both Mial's observations and her own on the effectiveness of these various contraptions at augmenting a shren's natural wings, and sends notes and contraptions all to Ehail.
She didn't expect any. (Mial nevertheless feels that he has Contributed to Research, and is very proud.)
He writes down a list of all the places he isn't allowed to go, just so he can scowl at it. His mother observes that Dragon Island isn't on the list. Mial emphatically declares that he wouldn't go there even if he could, because that's where Grandfather lives. Grandfather, as far as Mial is concerned, can keep his dumb island.
Koridaar gives him a hug.
It is more convenient to cast it on both of them herself. She does that, records the results meticulously, and sends them back.
But now that there's an analysis available, it's easier for Koridaar to think about the field of dragonish analysis. She invents variations. When she has one she likes, that actually seems to provide clearer results and not just slightly prettier ones, she sends it back to Ehail along with the information from Avar and Mial.
It's too delicate a system for Koridaar to feel comfortable messing with; they've gotten far enough to know that the actual state of shrenhood, the reason their wings are too weak to be of any use, is some kind of delicate magical adaptation to patch a condition that would otherwise just kill them. Without a much better understanding of how it actually works, she's reluctant to spend much time coming up with possible interventions which she has no safe way to test. There's no equivalent of oranges and lizards to be had here; it's live subjects or nothing.