Summary:Scientists have thoroughly drubbed an occult scientist, Karswell trying to publish about alchemy and such phenomena. One scientist dies, having fled up a tree and fallen off a dead branch--his face locked in horror. Another scientist realizes he may be next.
Commentary & Spoilers:The scientists figure out that the problem is a piece of paper with cryptic runes on it. It had happened to Harrington's brother. With only so much time, they manage to pawn the paper off back on Karswell who died from a fallen stone off a church though there'd been no workers at the time.
An interesting use of the mad-scientist trope. In this case, the sane scientists are the unethical ones. They've denied the occult without proof and even with proof don't support Karswell's findings. So in a sense, they, too, represent mad scientists. Further, they're not even sure that Karswell is behind the runes. Although it seems likely, they can't be sure.
"Had they been justified in sending a man to his death, as they believed they had? Ought they not to warn him, at least? 'No,' said Harrington; 'if he is the murderer I think him, we have done no more than is just.' "If Karswell is out for revenge, most readers probably feel his end is justified. He is the primary mad scientist. But what if he isn't? Then Harrington and Dunning are the only true mad scientists, a fact which may escape some readers. Perhaps that is the true horror here: Those, whom we assume to be sane and good, are actually the evil-doers.
Notes:1. What do the rune victims actually see or are visited by? A demon?
"One was a woodcut of Bewick's, roughly torn out of the page: one which shows a moonlit road and a man walking along it, followed by an awful demon creature. Under it were written the lines out of the 'Ancient Mariner' (which I suppose the cut illustrates) about one who, having once looked round--
walks on,Dog or human?
And turns no more his head,
Because he knows a frightful fiend
Doth close behind him tread.
"he got a dog with him, or what? Funny thing: I could 'a' swore 'e wasn't alone."2. The translation of runes is unknown; therefore, they have a mystery about them and are thought by some to be magical, inhabiting that great realm of the unknown/unknowable. No doubt, this is why James employs them.