A Practical Guide to Sorcery

Chapter 103: Illusion Chamber

Sebastien

Month 2, Day 3, Wednesday 10:40 a.m.

That Wednesday, Sebastien arrived at the Natural Science classroom a few minutes early, hoping to squeeze in some of her History reading before class started. She had a new schedule to optimize her productivity. It wasn’t much different from the old one, just more rigid and regimented, with less room for breaks, side projects, or aimlessness. It—along with the beamshell tincture—was allowing her to keep up with all her classes and projects, but afforded her barely any leeway. She hoped that a few stolen moments of extra work here and there would allow her to get enough ahead that she could occasionally take an hour or two to herself.

Ironically, despite her underlying fatigue, the hardest part of the plan was making herself get a full eight hours of sleep every night, in two four-hour chunks with only an hour of homework slipped between them. She had to force herself to cast her dreamless sleep spell and actually attempt to rest.

Sebastien stopped before the closed door to Professor Gnorrish’s classroom, frowning at the paper stuck to the door. “CLASS MOVED TO LIBRARY TUNNEL,” it read in big block letters. With a quick check of her pocket watch and a put-upon sigh, Sebastien spun around and hurried to the northern edge of the Citadel.

The crystalline tunnel between the Citadel and the library was dark, letting none of the outside light through with its normal shattered rainbows of color. A couple people at either end of the tunnel had opened a part of the wall that she’d never noticed before and were messing with something inside. Sebastien stepped into the tunnel warily, letting her eyes adjust to the gloom.

Gnorrish stood in discussion with a handful of other men and women at the center of the tunnel, though beyond the glint of a faculty token, it was too dim to make most of them out.

Sebastien sat cross-legged against the wall, imitating the handful of other students who had arrived before her. Her eyes slowly adjusted, but it was far too dim to read, so she tried to let her mind relax. She was still buzzing with energy from her morning dose of beamshell tincture, which tended to give her a feeling of bottled-up energy that needed to be released somewhere.

One of the men who had been talking with Gnorrish turned in her direction, his familiar silhouette attracting her attention.

“What are you doing here?” Sebastien blurted out to Professor Lacer, drawing the attention of the other professors and students.

He sent her a scathing look, and she ducked her head in an apologetic bow. “I meant, I’m surprised to see you, Professor Lacer,” she amended in a much softer tone.

“I am here to do a favor for a fellow professor, and, not incidentally, for my apprentice as well,” he drawled.

She wondered what kind of favor would require so many of the faculty.

Reading the curiosity on her face, Lacer simply said, “You will see,” and moved to stand nearby, his expression clearly stating that the conversation was over and anyone who disturbed him with idle chitchat would feel his wrath.

The other professors split up as well, at equidistant points along the length of the tunnel.

When Damien and Ana arrived, they looked around with curiosity. “What are we doing here?” Damien asked, the question aimed toward no one in particular.

“The whole tunnel is a simulation chamber focused on visual illusions,” Ana said. “I imagine there will be some sort of demonstration.”

Gnorrish loudly instructed the students to arrange themselves into groups and join a professor. A handful of other random students quickly joined Sebastien’s trio.

Sebastien rapidly tapped her fingers against her knee, letting Damien and Ana’s light chatter flow over her head.

Gnorrish walked slowly between the groups of students along the length of the tunnel, a ball of light floating above his head. His booming voice carried easily. “The next few weeks of this class will be an exploration of light. Or, more correctly, an exploration of the electromagnetic spectrum that includes visible light. It is an important research area in modern natural science for multiple reasons. Not only is light a freely available energy source for your spells—in some cases even more abundant or useful than heat—it is both versatile and powerful. I believe it has the potential to do so much more, and as it is considered one of the more difficult energy sources to channel, we will be spending extra time learning about it.”

Sebastien tracked Gnorrish’s slow pace with her eyes, unblinking, as if she could suck the knowledge out of the man with her eagerness alone. ‘The more I understand the subject through the concepts of natural science, the better control I’ll have with all magical applications that use light.’

Lifting his hands to the sky, Gnorrish paused, and then, with a dramatic flourish like a conductor before an orchestra, he dropped them.

An illusion sprang to life in front of each student group, not unlike what they were learning to do in Practical Casting, but somehow, perhaps because of the surrounding darkness, seeming more tangible. “Behold! One of the many utilizations of light magic,” Gnorrish trumpeted, throwing his arms wide with a grin.

The illusion spell displayed a stack of waving lines. They all seemed to move, flowing from left to right, with the ones at the top at such a gentle slope they barely rose or fell at all, and the ones at the bottom in a zig-zagging frenzy.

Sebastien peeked toward Professor Lacer, who had one hand pressed against a section of the tunnel wall and the other curled around his Conduit, his focus on the illusion hanging in the air before them. The other professors seemed to be doing the same, and, though the image in front of each group was almost identical, Sebastien thought theirs seemed more tangible than most. As if she would feel the lines if she reached out to touch them.

“Light is a form of energy, and it travels in waves like these,” Gnorrish said. “We can tell how much energy an electromagnetic wave has by the frequency—how many waves, from peak to trough, pass through a point in a set period of time. As long as light isn’t passing through substances with different densities, that means light with a shorter wavelength has more energy, while light with a longer wavelength has less. Light doesn’t have mass, so it’s not like water, but water can still be a good analogy. Imagine you’re in a boat on the ocean. Your boat is anchored, a single immobile point, while the water moves under and around you.” The illusion changed to show the side view of a cute little boat, floating atop deep water. “The peaks and troughs of each wave are always the same height. If each wave is so far apart that you rise and fall over them so gently it’s barely noticeable, with one wave passing underneath your ship every minute, you might say the waves were low-energy. Now, suddenly the waves get closer together, and as they pass under you, ten every minute, your boat pitches and sways so steeply you need to grab onto something to keep from being thrown off the side.” Gnorrish mimed a wild scramble for purchase against the pitching deck of a boat, to the laughter of many of his students. “Those are high-energy.”

Gnorrish stopped his wild flailing, grinning at their response. Professor Lacer switched the illusion from a boat back to the stack of waving lines, and Gnorrish pointed to a very small section of light waves in the middle of the nearest group’s illusion, which took on the appearance of a section of a rainbow. “Our eyes and brains are adapted to perceive this particular range of wavelengths, which we call ‘light.’ Can anyone tell me what’s special about light?”

Students shifted uncomfortably as his eyes roved over them, but no one spoke.

He looked to Sebastien. “Mr. Siverling! What do you think?”

She was confused for a moment, then realized it was a trick question. “The only thing special about it is that we can all see it, and we gave it a label called ‘light.’”

Gnorrish lifted his hands, bobbing them back and forth as if weighing something on an invisible scale. “That’s not entirely wrong, but not entirely right, either. The leading theory is that we see this part of the spectrum because it’s the most relevant for us. The majority of our sun’s radiation happens to fall within this range, and it manages to pass through our atmosphere without being absorbed or scattered. It could also be because visible light is the only set of electromagnetic radiation that propagates well in water, where it is theorized all the mortal species rose from. Yet another theory is that radiation in that part of the spectrum is easily stopped by matter. If we had evolved to ‘see’ using super-long wavelength radiation, for instance, which can pass through matter, we’d be bumping into trees and falling into holes because they’d be invisible to us! Or perhaps we wouldn’t be able to see at all, because the radiation would pass right through our eyes and out the back of our skulls.”

With another conductor’s wave, Gnorrish changed the illusion to show a tree standing before a huge eyeball, which was sliced in half so they could see its pieces and what was happening inside it. “Thousands of years ago, people thought that sight came from our eyeballs sending out tiny little information-gathering probes, which returned with the images we see.” The eyeball shot out little birds, which landed on the tree, and then returned, flying back through the pupil. “Of course, we know today that sight comes from light entering our eyes, passing through our pupil, and hitting the retina, which lines the back of our eyeballs and contains two types of photoreceptors.”

He went on to explain how rods allowed humans to see in greyscale in low lights. In brighter light, the red, green, and blue cones allowed the perception of seven distinct colors, with some ten million distinctions between individual shades and hues. “Did you know that human infants only perceive black, white, and grey?” Sebastien reached out, letting the tips of her fingers trail over the gigantic slice of eyeball, and almost jumped when it rotated away from her finger as if she’d actually touched it. She snatched her hand back, rubbing the tips of her fingers—which hadn’t felt anything—and looked at Professor Lacer. She wasn’t sure if she was imagining his almost imperceptible expression of smugness, but her attention was soon drawn back to the lecture.

“It’s not until about five months of age when we begin to see all the colors. Prognos children, however, see all colors from birth.” Gnorrish’s hand sketched out a wide arc, and the illusions morphed into bright light passing through a prism, splitting into the full spectrum of color. The rainbow beam stood out starkly against the relative darkness, revealing fine particles of dust in the air.

“This is what it looks like when you separate light into its different wavelengths, which is easy to do using a prism. Right on the edge, below violet, there is another color.” He paused dramatically. “Ultraviolet. Interestingly, it can be used for sterilization of bacteria and the newly discovered ‘viruses’ in lieu of sterilization potions, once thought to be working against ‘bad humors.’ Prognos, who have an extra two photoreceptors, as well as special oil droplets in their photoreceptor cells, can see ultraviolet, as well as distinguish between colors much more accurately than us. They live in a world of color that most of the other species cannot even imagine.” He paused wistfully for a moment, staring at the rainbow of scattered light. “Other creatures can see further on the spectrum in the other direction, known as infrared, which allows them to identify heat sources even in relative darkness, making them wonderful predators.”

As if reading Sebastien’s mind, Gnorrish answered her immediate question. “Attempts have been made to create spells that allow people to temporarily see beyond our normal visible spectrum, but they haven’t made it into general use, even among adventurers and the military, who would seem to particularly benefit from additional sensory abilities. Why?” He didn’t pause long enough for anyone to attempt an answer. “Basically, these spells have too many side effects, including synesthesia, where the brain confuses one sensory pathway with another and you begin to feel, taste, or smell colors. Other side effects are confusion, disorientation, and pain—in some cases, to the point of causing mental trauma. And in a few unfortunate instances, people have experienced rupturing of the vessels of the eye or brain due to incompatibility and overstimulation. Please do not experiment with this.”

He paused to let that warning sink in, meeting students’ gazes again to impress his seriousness upon them. “There are some potions that work safely, particularly for the infrared wavelengths, but they require an ongoing regimen over several months to adapt the brain to the expanded sense, and then continued upkeep to maintain that adaptation, which is very expensive and hasslesome, especially in the beginning.”

He turned back to the illusion, which morphed several times to show different examples as he walked them through the mechanics of refraction and reflection. As she took in the detailed visual examples, Sebastien felt her grasp on the concepts deepening beyond the surface-level understanding she’d once thought was all she needed. The illusion chamber made learning these somewhat abstract concepts significantly easier.

“Let us pause and think. How is this knowledge useful? What could you do with it?” Gnorrish asked.

“Invisibility spells,” a young woman piped up immediately. “You could just bend light around yourself so people see whatever’s behind you.”

A young man lifted his hand. “That works for illusions, too, making people think something is there when it really isn’t.”

Gnorrish nodded, pointing at the man as he replied. “That effect is encountered in nature through mirages, including the superior mirage known as the Fata Morgana, which have created illusions of floating islands that lure sailors to their deaths. It’s also why, in the morning, you can see the edge of the sun before it has geometrically risen above the horizon. Continue.”

Several others had their own ideas of varying obviousness.

“Shared perception spells, like you were saying.”

“The eagle vision potion and spell.”

“Dark-vision magic!”

“Some magical beasts are really attracted to the color red,” another young man piped up without waiting to be called on. “Maybe it’s the only color they can see? That’s important to know if you want to survive in the wilds.”

“Image-capturing artifacts,” Ana murmured.

Damien leaned forward. “Hidden messages! If you can tune a spell’s output to create a specific wavelength, you can have a receiver spell set up to recognize that exact wavelength—ideally one of the invisible ones—and you can use it to send pre-set signals. There’s a new communication device the coppers are using that probably works on those principles. It must!”

‘A temporary blindness hex,’ Sebastien thought. ‘You could interrupt someone’s sight without permanently damaging them just by keeping light from hitting their retina.’

A witch with a clear, jelly-like eel from the Plane of Water winding around her damp shoulder said, “Healing spells to mend or replace eyeballs. Or augmenting spells to improve the distance or ocular precision, even. Eagle vision could be permanent, if you did it right.”

‘It’s probably also applicable to wards against certain kinds of divination or revealing spells,’ Sebastien thought. ‘Reflect or redirect the magical waves. I wonder if my divination-diverting ward uses any of these principles?’

Damien raised his hand, speaking before Gnorrish had a chance to point at him. “There’s a shield spell that looks like a super-smooth silver mirror and reflects all kinds of energy attacks. Aberford Thorndyke used it to survive being thrown into a pool of lava. And maybe you could make a spell that turns infrared radiation into red light, to help illuminate the dark!”

Some of the students laughed, but Gnorrish only grinned wider. “Indeed, both very creative applications of the principle we’ve discussed.”

‘Sundered zones,’ Sebastien thought. She only realized she must have said this aloud when Damien’s head snapped around to look at her. She shrugged. “They’re obviously reflecting all light, to be that perfectly white, and magical effects can’t pass through them.” Supposedly. And yet an Aberrant like Red Sage managed to affect the world through its prophecies, despite containment.

Though Professor Lacer seemed uniformly unimpressed with the students’ offerings, Gnorrish was pleased. “All good ideas!” Gnorrish continued lecturing, explaining how refraction worked in mirages, rainbows, sunsets and sunrises, and various different lens shapes, with illusory illustrations for all of them, with ridiculous jokes peppered throughout the lecture to help them remember the mechanical details. He even used a couple of equations to explain things for the more mathematically inclined.

Then he let their groups play with the illusions directly, setting them various tasks with light sources, lenses, and different substances. Sebastien took charge, allowing no dissent, using hand motions and the occasional verbal request to Professor Lacer to change brightness, angles, and shapes. This interactive capability was the true feature of the illusion chamber. If only it didn’t require other professors to collaborate, putting forth their personal time and effort, perhaps it would be used more often.

Under Sebastien’s guidance, her group created their own simple eyeball, then both a telescope and a microscope, and some fun-house mirrors that morphed their reflections in various ways. They simulated infrared vision in one of the mirrors, and, at her request, Professor Lacer attempted to make a ball of light give off ultraviolet radiation, which was very strange. As Gnorrish had said, none of them could see it, except for a single half-prognos student in one of the other groups, but it caused normally invisible smears and splatters on their clothes and surroundings to stand out with a peculiar glow as the substances absorbed the ultraviolet and converted it back into visible light.

By the time class ended, her group was trying to produce their own miniature Fata Morgana mirage of a floating island in the sky, though they had some trouble with the delicate balance of the required conditions.

Sebastien had lost herself in it like a gleeful child playing with a fascinating toy and couldn’t help but be slightly disappointed when the illusion dispersed and the walls of the tunnel lightened, allowing the weak sunlight to come through in blinding rainbow-colored sprays and sparkles.

All the professors looked exhausted. Professor Gnorrish didn’t even have the energy to raise his voice or wave his arms about as he dismissed them. Even Professor Lacer had a faint sheen of sweat on his brow, but when he met Sebastien’s gaze and incandescent smile, the corners of his lips twitched up faintly in response.