The laboratory had been a fairly spacious room, about thirty feet by fifteen. Of its interior fittings nothing whatever remained. As the Professor advanced into the interior of the space his boots struck metal at every other step. He stooped and probed with his stick, and brought to light a twisted and shapeless tangle of iron, which might once have been the frame of a skylight. He examined it for a moment, and then cast it aside, with a nod of comprehension. The walls themselves still showed upon their interior surface the signs of having been subjected to an enormous heat. He poked about inside the laboratory for a short while longer, then came out and sat down upon the mound which had once been a cottage.