The table was spotless by that point. Not that it hadn't been before, and Twilight actually wondered how exactly the mare had decided when to stop, but she certainly had put effort in cleaning it. She headed for the door again, and Twilight took a moment to decide if she was supposed to follow behind her or not. She had already lost quite a bit of time staying there, not that she could have done much about it without risking being found out, was it better to go back to the room with the stallion or to go the other way?
She actually decided the best course of action, at least for the moment, was to do neither. She watched the mare walk out of the room, locking the door behind herself, then through the glass she watched her enter the other room, and return to the main laboratory. Then, sure she wasn't about to come back, she focused on the crystal contraption hanging above the table. This time, using her magic too, not just her eyes. A full scan of the thing, to start with.
It hadn't been cleaned as throughly as the table, much to her displeasure. It was clean, yes, but some small traces of blood were still picked up by her magic. Judging by the mechanism she felt above it, the sharp point wasn't a mere catalyst to direct the spells flowing through it, it was meant to embed itself in the test subjects. It made sense, but it wasn't exactly a pleasant revelation. She moved along with her investigation.
Wires and perhaps tubes of some sort stretched out from inside the thing and up into the ceiling. It was possible something was injected into the ponies it was used on, or at least could be injected. She focused on what was there instead. As she'd thought she'd seen, there did appear to be something within the main Crystal. Magic bounced off and passed through it like it would through particularly thick and magically charged fog or smoke. Flying up to get a closer look, Twilight finally realised what it was, or at least what it most likely appeared to be. A strand of Nightmare Moon's mane, encased within the crystal.
Already up there, she had a short flight around the thing to get a better look from all angles. Other sharp pieces of crystal jutted out at angles just as sharp, all of the same black and blue colour. She could probably figure out the exact pattern the design was based on, but it wouldn't have served much purpose for the time it would have taken her to do it right there. And for once, she had very little interest in ever replicating the tool. Although, on second thought, perhaps something similar could have medical uses.
She focused her magic on the table instead, having analysed the spells cast through the crystal as much as she was able to. It had been insightful, but only so much. She already knew experiments were happening there, and the kind thereof. She knew a little more about them after that, but what she was most interested in, as much as it disgusted her, were the results. That was what her ponies would need to be preparing for.
She didn't like what she was about to do, but she knew it was for the best. Trying not to let her attention dwell on any of it more than strictly needed, she began to analyse what had been on the table before. It wasn't properly rewinding time, it was closer to evoking a memory of what had happened. A lot of it, as she'd known would be the case, was pain. Some of it was worse.
Thankfully, like she'd realised while listening to the two unicorns talk, more recent instances of the table being occupied had led to less damaging results on its occupants, and even through all the suffering accumulated there through time it didn't take too long for her to draw out a ghostly image of what those results had been. She didn't like it, for entirely different reasons from what had made her dislike what else she'd felt there. But at least she would be able to tell she'd found what she was looking for if she ran into it.
A moment later she had another look around, then carefully left through the door opposite the one the unicorn had gone through.