Since I was little I had been aware that my sensitivity to mana was frankly absurd, according to my teacher this was probably related in part to the race to which I belonged, in any case, this was one of the main reasons why I was such a good alchemist.
In any case, my profession as a magician and alchemist had only to increase my sensitivity to mana even more than given the current circumstances where Desmond was performing ability of which he had not fully mastered; These two factors basically allowed me to "See" Desmond's internal flow of mana.
At this moment his mana was moving in a pattern that was incredibly similar to me as I had seen it at least a few dozen times in the last few days, from Desmond's mana core located in the center of his chest, waves of mana emanated from the constant way; These waves were emitted with a constant length, frequency, and intensity and covered Desmond's entire body.