Here are some of the key elements that contribute to the tone:
* Gothic Horror: The story is steeped in a sense of gothic horror, with a dark, decaying setting, a mysterious and ancient object (the temple and the "god"), and a sense of foreboding and impending doom.
* Psychological Horror: The story also explores the psychological state of the protagonist, Joseph, and the effects of his loneliness, isolation, and obsession with the "god". This adds a layer of psychological horror, as we see his descent into madness and the power of his own belief.
* Fear of the Unknown: The story deals with the fear of the unknown and the unsettling power of ancient, unknowable entities. The reader is left to wonder about the true nature of Sredni Vashtar and the implications of its existence.
* Religious Subtext: The story also touches upon themes of religion, faith, and the power of belief. The protagonist's unwavering belief in Sredni Vashtar, even in the face of disbelief from others, highlights the dangers of blind faith and the potential for it to become destructive.
* Unease and Dread: The story creates a palpable sense of unease and dread, leaving the reader on edge throughout. This is achieved through the use of vivid imagery, unsettling descriptions, and the constant feeling that something sinister is lurking in the shadows.
Overall, "Sredni Vashtar" is a story that leaves a lasting impression. It is a chilling exploration of human fear, obsession, and the power of belief, with a tone that is both unsettling and profoundly disturbing.