One common theme is the unknown. For example, in many Lovecraftian stories, there are unknowable cosmic entities that drive the horror. Another theme is madness. Characters often descend into insanity, like in 'The Yellow Wallpaper'. Death is also a common theme, whether it's a violent death or the fear of impending death as in 'The Masque of the Red Death'.
One great weird horror short story is 'The Yellow Wallpaper' by Charlotte Perkins Gilman. It's about a woman's descent into madness as she is confined to a room with yellow wallpaper. Another is 'The Tell - Tale Heart' by Edgar Allan Poe. The narrator's obsession with an old man's 'evil eye' and his subsequent actions are truly creepy. And then there's 'The Monkey's Paw' by W.W. Jacobs, which shows how a simple wish - granting object can bring about terrifying consequences.
I'm not sure specifically who the author of the 'book of weird short stories' is. It could be an anthology with multiple authors contributing their unique and strange short stories.
They often have a sense of the uncanny. For example, they might have strange settings like an otherworldly city or a forest that defies the laws of nature.
The unknown is one of the scariest elements. For example, in a story where there are strange noises in an empty house but you don't know what's making them. It could be anything from a ghost to some kind of monster. Another scary element is the feeling of being trapped. Like when the characters are in a spooky place and can't get out, such as in a haunted cellar. The last one is the element of the uncanny. When things seem almost normal but there's something subtly wrong, like a doll that looks like a normal doll but has an evil presence.
There was a doll that was found in an antique store. It had a very strange appearance, with its eyes that seemed to follow you around the room. A girl bought it thinking it was cool. But at night, she would hear it whispering. She couldn't make out the words at first. One night, she woke up to find the doll sitting on her chest, its face inches from hers, and it said 'You're mine now' in a raspy voice. She threw the doll out the next day.
Well, there might be a story where a girl discovers a door in her attic that leads to a parallel world filled with talking animals and plants. This world has its own set of rules and she has to figure out how to get back home. In the 'book of weird short stories', such unexpected and fascinating scenarios are often explored.
One of the best is 'The Yellow Wallpaper' by Charlotte Perkins Gilman. It's a disturbing tale of a woman's descent into madness, with the strange yellow wallpaper in her room playing a central and eerie role. The story uses the setting and the woman's psychological state to create a sense of the uncanny.
H.P. Lovecraft's 'The Call of Cthulhu' is also great. It has this Lovecraftian horror with the ancient, otherworldly entity Cthulhu. The way he builds the atmosphere of a world filled with cosmic horror that is beyond human understanding is what makes it stand out.