For one, the desk that he so routinely sat at had grown to something like the size of a townhouse before him.
For another, he was having difficulty feeling his arms and legs. In fact, for some inexplicable reason he was finding it hard to believe he had arms and legs at all. This, of course, was ridiculous, as he had just that morning confirmed the existence of those exact limbs in question through a drawn out fight with his tunic for the duty of appearing kempt.
Alas, as the moments passed and the perspective predicament did not become any less perplexing, the professor did grow certain that he indeed no longer owned any limbs.