Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
Macabre, Grotesque, Gothic
Macabre
For those of you who don't speak French, macabre isn't what a magician yells as he reveals a trick. Macabre, as defined by the illustrious Merriam-Webster Dictionary, is an adjective used to describe anything involving death or violence in a way that is strange, frightening, or unpleasant, and tends to produce horror in a beholder (source). We'd definitely say that The Monstrumologist produces horror in a beholder. How does Yancey write in a macabre fashion? Word choice, Shmoopers. Word choice. Check it:
He was covered head to toe in the blood-flecked goop, the smell of it more pungent than that of the rotting flesh upon the table. The tiny Anthropophagus flipped and smacked inside the jar, smearing the glass with amniotic fluid, clawing at its prison with needle-size fingernails, mouth working furiously in the middle of its chest, like a landed fish gasping upon the shore.(1.116)
Yancey chose some of those words quite deliberately, which takes the description from just yucky to shudder inducing. Using "pungent" instead of "stinky," for example, or "smearing the glass with amniotic fluid" rather than "painting the jar with its birth juices". Okay, that last one was pretty macabre, too, but you get the point.
Grotesque
There are a lot of things in this book that can be described as grotesque, but it's not just the Anthropophagus that is deserving of that adjective. The tone of the book is grotesque as well, leaving you feeling a bit like you should wash your hands after you've put it down.
The reverend, whose body remained more or less intact, had captured our attention as the locus of the slaughter, but all around it, like shards thrown from a grisly centrifuge, upon the walls and floorboards and even the ceiling above our heads, were fragments and scraps of human flesh, unrecognizable effluvia cemented by blood to nearly every surface: tufts of hair, bits of entrails, splinters of bone, shavings of muscle. In some places the walls were so saturated they literally wept with his blood. It was as if the child had been shoved into a grinder and then spewed out in every direction. Lying but a few inches from the doctor's right shoe was the severed foot of the boy, the only recognizable portion left extant by the marauding Anthropophagi. (8.46)
In this quote we can practically feel Will Henry being repulsed by what he's seeing around him, and as readers, we're forced to share the sensation. Yancey wants us to by horrified by the scene that he's painting, and he doesn't pull any punches in attempting to convey the awfulness the Anthropophagi are capable of.
Gothic
When you hear the word "gothic" you might immediately think about the teens that wear heavy eye makeup and lots of black leather, but that's not quite what we're going for in this case. The tone that Yancey sets in The Monstrumologist is gothic because it evokes a sense of slow-burning fear; he describes strange and frightening events in mysterious places, and we're left feeling haunted.
A good example is when he sets the scene for Dr. Warthrop's visit with Captain Varner at the Motley Hill Sanatorium. An insane asylum is the perfect gothic setting, but then he adds in an air of abandonment and decay, and we get this:
We had not traveled far down the main street of Dedham before Warthrop turned his horse down a narrow lane that wound through a dense stand of poplars, at the head of which a small, inconspicuous sign hung upon a rusting steel pike: MOTLEY HILL SANATORIUM. Trees and tangles of vine and weed crowded upon us as we proceeded, slowly now, up a rise of ground. The woods closed around us; the canopy drooped lower and lower, blotting out the stars, as if we had plunged into a dark and winding tunnel. There was no sound but the steady clop-clop of the hooves upon the hard-packed dirt. No chirp of cricket or croak of frog. Nothing disturbed the profound and eerie silence that did not so much descend upon our plunge down this Cimmerian path as slam hard down upon our heads. Our horses became jittery, snorting and stamping as we climbed. The doctor appeared quite collected, but for myself I was not faring much better than my little mare, both our eyes darting in the growing blackness. The trail—it hardly could be called a lane anymore—finally leveled off, the trees drew back, and much to my and my little mare's relief, we emerged into an open, if overgrown, expanse of moonlit lawn.
About a hundred yards directly ahead stood a house of the Federal style, white with black shutters and towering columns guarding the front. The windows were dark and the property had a deserted feel about it, as if its occupants had long ago fled to happier climes.
[…] Upon closer inspection, the house was a shade or two closer to gray than white; it had once been white, many seasons ago, but the paint had faded and begun to peel. Long strips of it hung from the bare, mildewed boards. The windows had not been washed for months. Quivering spider webs clung to their corners. (6.2-6.7)
Tell us that passage didn't make you get up and turn a light on and we'll feel like giant chickens because that's totally what we did.