Roxanne reminded herself that she had used her wand without incident just a few minutes ago, and that there was no reason to think there was anything wrong with it now. Wands often reacted differently when someone other than their owner was using them. And her intention in repeating this exercise was to determine that it was in fact a problem with Glendga, not the wands. This had just been proven, to the degree that there was probably no need to continue the demonstration.
She continued it anyway, taking the other woman's wand and holding it for a moment to mentally catalog the similarities and differences, like she always did when using someone else's wand - weight, balance, flow... they seemed to have the same type of core, that was interesting. Then she took a cloth bandage from her purse and placed it on the desk as far from the former handkerchief as possible, and, concentrating, cast the warming charm.
It was nearly hot enough to burn when she touched it, an easy difference to attribute to using an unfamiliar wand. But something was clearly wrong with her patient. It wasn't the wands, it wasn't the setting. It was Glendga.
Roxanne's expression turned even more thoughtful and serious as she exchanged wands again with a murmured "thank you." She spent a few fruitless moments over the melted handkerchief, unwilling to discount even the unlikely possibility that the readings would be different this time, then turned to Glendga. "I want you to tell me how long you've been experiencing these or similar symptoms," she said. "Have they occurred anywhere aside from this house and the grounds? Perhaps we should sit," she added, more gently than usual. The other woman looked less than happy, and she couldn't be faulted for it - the thought of your magic going wrong was terrifying. But at least the way it went wrong seemed fairly consistent. That had to be a good sign.