They say that adventure is filled with long periods of boredom punctuated by moments of sheer terror. I had every intention of minimizing the time spent in terror... and I had so many thoughts bouncing around in my head, that I could be locked in an empty, unlit room for a month and be thinking of novel connections and new ideas without pause the whole time.
(I found it privately amusing that I was being an 'adventurer' in more ways than one. The word itself originally applied to ships, which, instead of merely running cargo along an established route or being hired to carry something from point X to point Y, actually had the captain buy some cargo outright to carry on their journey, in hopes of at least offsetting costs. Doing so 'added' to the profit of the journey, the 'venture'. I knew all this because when I'd been in high school, I'd put my savings into buying HBC shares - the Hudson's Bay Company, the oldest remaining chartered corporation still running, which had once governed a greater land area than the Roman Empire had at its height. Its official name was still the "Governor and Company of Adventurers of England Trading into Hudson's Bay", and since I wasn't the governor, I'd had a legitimate excuse to call myself a 'real adventurer' since before I could vote, as long as I didn't mind making a joke depending on an absurdly obscure piece of etymological trivia.)
Naturally, I had no intention of simply sitting still during the trip. While it was a relief to be able to hand over the paperwork to the Dairy's new acting director while I was gone, I was still bringing along a couple of projects likely to keep me distracted whenever I didn't have anything better to do. One was classified SHORT ROUND; other than leaving some backup notes in Canterlot, I was bringing the whole setup with me. I'd raided Canterlot's royal research museum, its institutes of higher learning, and even a few rich geology buffs, for samples of every different type of crystal I could find. I wanted to see if I get get a quantification of how much magic they could store - and once I had that basic measurement under my belt, I could start poking around with things like how quickly any of them could gain or lose magic, how long a light-diamond would shine on a given charge, and all that other lovely basic undergrad-level physics stuff.
Of course, since the only reliable way I currently knew to charge up a crystal was from a cow's horns, and none of my fellow bovines had agreed to come along, the only way I had to charge these crystals for testing was to use the magic stored in my own body. Since that involved my mind going bye-bye for a few moments, this also meant I had to cobble together some sort of mechanical gizmo which would automatically disconnect the crystal from my horns while I wasn't able to. But even more limiting was the fact that I only knew of two ways to recharge my body's magic - slowly from Equestria's general magical field, and quickly from other cows' horns. Since I didn't want to run out of the magic that kept my brain in good working order once we left Equestria proper and entered the rainforest, I wouldn't be doing any of these experiments there.
So, for the more tropical part of the trip, I'd also brought my equipment for CAT WHISKER, my attempt to put together a working radio receiver. I was pretty sure I had a transmitter, at least one good enough for Morse-code type wireless telegraphy; but that didn't do me much good without something that could pick up what was being transmitted. I'd once been a cub scout interested in electronics; I'd ended up with a ham radio license; and I was pretty sure I'd figured out at least a few designs for a crystal radio that would work. All that I was missing was a single component: a diode, or as the Brits put it, a rectifier, something that would let electricity flow through easily in one direction but not in the other. Equestria didn't have a semiconductor industry; and while they had air pumps, such as to blow up balloons, they weren't good enough to create the sort of vacuum that allowed vacuum tubes. So I was going back to an even earlier technology: touching two different materials together, running current through them, and looking for a combination that worked well. The classic version was to take a crystal about the size of a knuckle, such as germanium, and to gently press a thin wire (the "cat's whisker") against a particular spot on it with a particular pressure. Unfortunately, even back on Earth, this had been an incredibly fiddly process - even for crystals of a type known to work, most particular crystals had flaws rendering them useless for this purpose; and each crystal that did work had a particular sweet spot the whisker needed to touch, and the pressure it was touching with could be neither too low nor too high. Here in Equestria, the problems were magnified - for just one thing, there was no 'Germany' to name germanium after. Much more importantly, significant aspects of physics were different - I still hadn't figured out the reason everything everypony looked at had outlines, only that it was a physical phenomenon which persisted into photographs; when meant that photons behaved differently; which meant that the overall electromagnetic field those photons were a part of behaved differently; which implied that the subtle electric properties of any given substance could easily differ from those on Earth; which meant that even if I found a chunk of germanium, it might not do what I needed.
To give a sense of the scale of the problem - I could either press a metal whisker against a crystal, or two crystals against each other. I easily had a dozen different types of whiskers, and a hundred crystals. For each crystal-wire combination, I had the choice of picking exactly where on it to try (call these parameters 'latitude' and 'longitude'), how hard to press the whisker, and depending on what configuration I used for the rest of the radio, up to four different variables to adjust that altered arcane properties such as 'inductance' and 'capacitance'. If I was trying a crystal-crystal combo, I also got to choose how large an area of facet to have push together. Multiply that by the number of crystal combinations... and I might end up having to learn many more than 10,000 ways to not make a radio before I made my first one. I could only hope that there were actually a large number of settings which could do the job, and that I'd stumble onto at least one of them sooner rather than later.
And, of course, there was always the possibility that I wouldn't be able to make a functional radio at all. In a universe where it was a reasonable hypothesis that one or more local mammals were able to shove around major celestial bodies, it was entirely possible that the closest I'd ever get to wireless was through a crude, mechanical switching of terahertz-level pulses - that is, blinking lights on and off at ponies.
I really wanted to do better than that.
The Alicorn didn't head due south straight away. Micro Scope said that she had a relative in Stalliongrad, an archaeologist who'd done some work there in decades past, and who might have some unpublished papers and maps that could help us. Since this particular expedition was planned to be a peaceful intelligence-gathering one rather than investigating dangerous bands of diamond dogs, and since Safe Guard needed some practice running the Dairy, and since Micro was interested in collecting some fresh specimens from the rainforest while we were there, he stayed behind and she came along. I was going to miss the fast-paced games of chess with Safe - postal chess through the Dairy network, while we were still in range of it, was fun in its own way, but not quite the same.
As we neared the city, Micro admitted that while Copper had helped inspire her own interest in the sciences, he was also something of a character, and we'd probably have the best chance of getting any useful information out of him if she went to see him by herself. The crew had every intention of staying aboard the Alicorn for the whole trip, come what may; when left me, Red, the four pups, and Amethyst at loose ends for a few hours. (Before I'd left, I'd been going back and forth over whether or not I should bring John, Paul, George, and Ringo. It should be a reasonably safe trip, but it was still a trip into semi-unknown jungle. I'd finally simply talked to Amethyst about it - and I really do mean 'to' her, since she didn't say a word in response. By the time I finished describing everything I was thinking, she had simply started packing her things, tucking various extra items into her vest alongside her crystal-snacks, and when the time came, she carried the pups to the boarding ladder. It was rather hard trying to puzzle out the thought processes of a woman who never used two words when one would suffice, and preferred none to one.) I could have stayed aboard myself, doing the same experiments I'd been doing on the trip there and would be doing when we left... but that seemed a bit silly to me. So we all went down to do all the stupid tourist stuff that people going to Stalliongrad did.
While the city was no Manehattan, it did have a selection of museums and theaters, some parks, a planetarium, a whole lot of industrial infrastructure including a canal and railways. But what we ended up spending almost all of our time at was the circus. With Red the pegasus to show we were harmless, the four pups got stuffed into a quadruple-seat stroller pushed by the bipedal member of our party, and there was juggling, and clowns, and acrobats, and contortion, and non-sapient animal acts like juggling bears... all of which were part of a story. It was like going to the theatre for a musical, only with more random interruptions with seltzer-squirting pony-clowns. I was unfamiliar with the fable, and tried to focus on the details of the plot - it was something about a villain who captured good creatures and transformed them into monsters, such as turning a quartet of ponies into dragons to pull his chariot, and who wanted to pull a Nightmare Moon to create eternal darkness; and who was defeated by a rainbow of light brought by Applejack the earth-pony, Spike the baby dragon, a unicorn named Twilight, and a collection of less familiarly-named compatriots. Amethyst and the pups seemed to enjoy the circusy trappings and animals, and Red perked up at the songs and ate more snacks than the rest of us combined. I didn't really have any way to find out how old this particular story was, and how much it might have been updated since Princess Luna's return.
We picked up an embarrassing amount of souvenirs... and the pups got some rather funny looks from Micro when we got back and she saw them in their t-shirts.
"So how'd it go?" I asked.
"Could have been better, could have been worse," she hedged. "I've got a trunk with some of his papers and maps and so on that he thought might help us. I'm pretty sure there's more he could have said, but didn't want to talk about to me."
"Shall I go have a visit in my more official capacity?"
She shook her head. "I don't think that'd work. I mean, I'm family, and this is as much as he was willing to help me out - I can't imagine that his attachment to the government bureaucracy is stronger than to his own kin."
"Well, it's some, at least, and hopefully there's more in there than we already had. Want any help going through it?"
"I think I shall try sorting through it all first myself, to see if some proper organization can narrow the range of what to focus on."
"Fair enough. You know where to find me if you need anything."
When I began dismantling the SHORT ROUND gear to start fiddling with CAT WHISKER, one of my first tasks was to get a baseline reading, of a would-be diode that didn't actually do any good. The simplest way to do that was to stick two crystals of the same type together, such as my favorite sapphires; which, pretty much by definition, would pass current as easily in one direction as the other.
Except, in this case, the readings I was getting not only weren't the same in either direction - but, according to my test instruments, I was actually getting more power out of the component than was going into it! Obviously, I was doing something wrong - possibly even my electrical meters themselves were faulty. So I put the circuit I was testing aside, rebuilt it from fresh components, pulled out the backup meters, stuck in a new pair of sapphires - and, this time, got exactly the null results I'd originally expected to see. I didn't want to have a similar problem cropping up in the future, so I tried the original test equipment on the new circuit - and got the proper readings. I started swapping in components, and everything was fine - until I plugged in the first pair of sapphires. Again - no current at all passed in one direction, and something like twice the input current came out the other way.
I temporarily ignored the impossibility of those results, and swapped one of that pair for one from the other pair, and still got the super-diode effect. I tried the other two - and got the ordinary null result. I tried the remaining combinations, and whenever one particular sapphire was used, got the effect, but didn't with any others. I tried pairing it with a ruby, and it still worked... for about two more minutes. Then the effect disappeared entirely.
I took a moment to set my tools down and think. As far as I knew all my mineral samples were the same; all that I'd been doing with them since I got them... was...
... charging some of them with varying amounts of magical power. Including one test sapphire.
I unpacked the SHORT ROUND gear I'd just put away, stuck a sapphire into the timer-box, stuck my horns in, and when my head cleared in a few moments, took that sapphire and plugged it back into the CAT WHISKER test circuit. The results were obvious and immediate - it was once again a super-diode.
I put everything down very carefully, and then went to unlock the safe containing the encryption keys - I wasn't entirely sure what I'd just found, but if it had even a fraction of the potential I was imagining, it was more than worth using up a page of the one-time pad to send the details back to the Dairy at Canterlot, just in case the Alicorn went down in flames in the next couple of minutes. I handed the encrypted text to Red, who flew down to what the maps said was a nearby stringer, who'd be able to pass it along towards the Pegasus Express, and on from there.
While Red was out doing her thing, I thought, and I thought, and I thought some more. One of the main limitations of Earthly crystal radios was that they got all of their power from the radio signal itself, which meant a very limited range - depending on the transmitter power, most likely a scant few tens of miles, or less. But if a magically-charged crystal could serve not just as a diode, but as a built-in amplifier (at least for as long as the charge remained)... and, now that I thought about it, there were a few other electronic uses to which such an amplifier-crystal could be put... including to the makeshift transmitter design I was using. I took out my drawings of circuit patterns for transmitter and receiver, came up with a new symbol for an amplifying-diode... and tried laying out a new set of designs. They were obviously no good, so I grabbed more paper, and tried again. And again, and again. Eventually, I figured out something that was marginally satisfactory - but could still be made better. Red came by and talked for a bit, and I waved in her general direction and muttered something positive. Amethyst came by, and I adjusted the way I was working to make room for the pups to nurse. After a while, she brought them back to nurse again. I started putting together some physical implementations of some of the circuit designs I'd been drawing, so that I could start measuring how well the super-diode effect worked, and for how long, at various voltages, currents, and other electrical properties. I refined. I modularized. I noticed my head was starting to twitch to the left every time I had a useful thought - unfortunately, it was also twitching to the left when I had a non-useful thought, too. I put a transmitter circuit at one end of my workbench, a receiver at the other, and got a satisfying buzzing from the latter. I asked Red to ask the crew to do some woodwork to put together some cases. I dug up some manuals on how the ponies had learned were good ways to build buttons to be pushed by hoofs, but not by accident.
Finally, I folded a set of wiring into one case, latching it closed; then did the same to a second. I grabbed one and carried it outside, onto deck - it was night. I didn't try wondering which night, I just hunted down Red, who turned out to be back sleeping in the stateroom behind the room I'd been working in. "You've memorized pulse-code, right?" I asked, as she blinked blearily up at me.
"Uh... yes?"
"Here," I shoved the milk-jug-sized box towards her. "Put the earphone in, and start flying away, so we can see how far away you can still hear the pulse. You should be able to pulse back with that button... wait, do you need your hooves to aim while you're in the air? Hold on, I should add a strap to the case so it can hang around your neck, so you only need one hoof. Or your chin - well, I'd need to move the button, but this is a circuit test instead of an ergonomics one, so that can wait for the next surface redesign. Which I'm trying to hold off on until I can see if I can put the crystal in series with itself without generating a feedback resonance that would end up shattering the crystal if not exploding it - don't worry, this design doesn't have anything of the sort - or if I'm going to definitively need more than one, in which case I'm going to try to put them all onto a single removable card for easy replacement." My head twitched left. "Why are you still here? Do you need to grab a bite to eat first to make sure you have enough blood sugar? I'm not sure how far you'll need to fly - this might stop working at any distance more than the length of the airship, though I'm expecting it to be a few hundred yards, which is reasonably decent for a first-generation walkie-talkie. Or flyie-talkie, in your case, though that doesn't rhyme at all and would make for terrible branding, if we ever go commercial, which I rather doubt we should any more than we have with Chekov. I think we have some cake frosting in a tube in the pantry which you could suck on to get maximum calories in minimal time-"
She finally used both hooves to clamp my muzzle shut. "When's the last time you slept?"
"Mm mph." She carefully loosened her grip on my mouth. "I dunno. I've been kind of focused the last... while. What time is it?"
"Three in the morning."
"Okay. ... What day is it?"
"Right - that's it. Here. Get onto my bed. There you go. Lie down. Hand me that... whatever, and I'll just put it down here out of the way. Close your eyes. If you're not asleep in five minutes I'm going to get Micro to dose you with - anything that'll knock you out. The pups can drink bottled for a while. Don't make me sit on top of you or tie you down - you know I can and I will."
"I think I left my soldering iron on..."
"I'll take care of it. Now: sleep!"
I slept.