“Who would like to explain this principle?” the professor asked. He was greeted by utter silence. He glanced around the room at the students and repeated, “The principle of contagion? Can none of you explain it?”

Emery, the youngest student raised his hand. The professor nodded at him and he rose. “Sir, the principle of contagion maintains that… if something has been in contact, no matter how tenuously or how briefly, it will always remain in contact. It’s used in a variety of spells, especially those that connect people to property.”

“Yes,” the professor said. “It’s also used a great deal in magical forensics.”

Emery remembered that day like it was yesterday. It was the first time he’d heard of magical forensics – at least in more than a periferal sense. His father’s disappearance had prompted mention of forensic mages; only that they were unavailable.

Now he was a forensic mage himself and working on cases much like his own father’s disappearance. His magic did not use the principle of contagion. He hardly used the principles at all. Most of the time he used the gifts of semi-magic that he was gifted with.

“How can you read the trauma at a scene without casting a spell?” Hassett asked over his shoulder. “I mean… you don’t have a wand, so then you didn’t cast a spell.”

“Well,” he began. He looked down at his shoes and then up at the warden. “I use a preliminary spell that doesn’t require a wand. It gives me a general idea of the trauma that occurred in an area.” He did draw his wand then, at least for appearances. He even murmured as if he was casting a spell. It was easier to pretend than explain off-magic.