Harvest 23rd 3472 EE

Oh yes! Go Celly, go Celly! I finally have a unifying hypothesis, and it has opened many methods of non-magical flight. And we may have a lead on how to provide a substitute horn for non-unicorns, allowing them to cast spells with their innate magic. But more of that later.

I mentioned the rising of hot air, the rising of certain unheated vapours such as philostogen, a burning gas that forms when acid is run through metal filings, and the airflow over a pegasus wing, all of which create a lifting force on objects. It came to me in the tub; it has been known since ancient times that things float in water if they are lighter than the volume of water they displace. Even a heavy clay pot can float if the space inside it is empty making the overall weight less.

Air also has weight, observe windmills, or the pressure against your wings. What the same thing can happen? If philostogen were a gas that is naturally less dense than air, it would rise as a bubble of air in water. But that does not explain how heated air could do so. Wagon wheels do though. Heating it fits the metal band that holds the pieces of a wheel together on. This causes the band to expand, so it slips on over the wood. When it cools, it shrinks back to normal. Once again air could expand when heated, meaning less air in a volume.

Note to self: Visit the smith for some new horse shoes, something with a gold chased sock would work. Second note to self: Ask Luna about some sort of sticking charm powerful enough to replace horse shoe nails, I don't think any-pony enjoys getting hoof piercings any more than I do.

The lifting force of a wing was a tough one, but I think I have it, from watching and feeling my wings pass through thin cloud as I glided. The cloud, and air flowing over the top went faster, and travelled a longer route over the convex wing surface. Once again the air was stretched over a larger surface, which meant it had to be less dense.

Atlas is helping me to quantify these observations, providing us with formulae to describe the sizes of effect we need to create pony-carrying devices. When he can drag himself away from making goo-goo eyes at Blue Mane. Snicker. After all, what with getting materials to generate philostogen, and igniferous oils for heat sources, not to mention chemicals for varnishes, he has a perfectly valid reason to spend lots of time down at the Alchemists shop. Smirk.

I shouldn't tease. But the way he gets all embarrassed when I mention it is too cute! No, bad Celly! Even if I was a unicorn, I'd have no right to go horning in on his love life, not that I think they've gone further than a few nuzzles and cuddling. I will have to rise above my baser impulses, which should be easy for a pegasus.

Anyway, after some research, and a lot of messing about with varnishes and glues, we have taken fine silk, though a fine grade of linen or cotton works as well, and applied a lacquer with pegasus hoof clippings dissolved into it during the preparation with aqua fortis. This seems to provide a suitable material for constraining air or philostogen, though less so for the latter.

The cloth can be sewn into bags before painting, which minimises leakage. Luna remarked how our test model, lit from below by a wad of cotton steeped in igniferous oils, looked like a small moon, and so we've started calling them balls of Luna as a joke. It used heated air, and was open at the base, while our Ball of Luna that contained philostogen had to be sealed. It was also far more expensive to fill due to the acids needed to generate philostogen.

We tested a larger model using the heated air method and I followed it up a goodly distance in open sky. The sun was bright, and I started wondering if the sun is a ball of philostogen, surrounded by it's own shell of air. After all, we can see the moon is a sphere from the changing phases, and any pegasus who flies up high enough to where the air thins out can see the curvature of our own world.

Well, not every pegasus, I found I could use that new ability to manipulate clouds to constrain a pocket of denser air around me, but the view was fantastic. I could see the boundary of the air, like a blue horizon, the clouds so far below they looked like snow covered mountains, part of the ground. I wish I could have carried a sketch pad with me.

We've continued testing that cloud controlling spell, and it's so well synchronised with pegasi magic it's contagious simply from contact. I think within a few years every pegasus will have the power, and it will pass on to new foals. Maybe one day we'll build chariots of cloud, or some flying machine that will work without air and travel beyond the air, visit the moon and sun for ourselves.

I worked out a way to deduce their distances once, using the angles of their shadows at a particular moment, and hourglasses and my own speed to synchronise the measurements. According to my calculations, and Atlas's the moon is hundreds, and the sun tens of thousands of times further away than the width of Equestria. Even at my top speed it would take days to reach the moon, and years to reach the sun.

Note to self: When visiting the sun, would require some sort of heat protection spell or clothing. Investigate. Maybe we should just go at night instead.

Speaking of chariots, Luna has been busy and it's produced results. We now have a rune-set we can engrave into a chariot's wheels and traces. Once empowered, when a pegasus wears the traces, her flight magic is shared with the chariot. I'm going to carry Luna in our test vehicle up as high as I went, and she can do some sketching. Who knows, if things go as well as I hope, I may be able to give Atlas and Blue Mane a unique trip for their honeymoon.

I just wish we were having as much luck at finding alternatives for a unicorn horn to focus magic other pony races' magic. We've managed to come up with a design, a short stick of magically resistant wood, such as oak or rowan, or gold, combined with a central core of magically conductive material. Pegasus and phoenix wing feathers, a thread of unicorn mane, dragon bone, hundreds of others. We've tried them with mixed results. What seems to work for one pony utterly fails for another.

It's looking more and more like each Wooden Alternative horN Device or WAND (nifty acronym, I thought) would have to be custom crafted. Not impossible, but we'll need to change our research priority to identifying and typing magical energy flows, so we can simplify the process enough to be practical. I think another month's work, and we'll have a whole slew of demonstratable alternative flight methods to show the Academy, and enough results on the WAND project to show it's possible. I can't wait!