"definite presentment of a fiend...."
See in text (Chapter Two)
In legal parlance, Utterson’s specialty, “presentment” is used to describe the formal setting forth of a case, argument, or document. Here, the word seems to mean something closer to presentation, as in image. “Presentment” in this case might also be close to “presentiment,” which fittingly refers to a feeling of foreboding and imminent evil.
See in text (Chapter Five)
A “cheval glass” is a rotatable, full-length mirror. The events in subsequent chapters may reveal why Dr. Jekyll would need such a device.
"it said complainingly...."
See in text (Chapter Eight)
The use of the pronoun “it” is intriguing. On one level, it is the accurate pronoun to attribute to the “voice” within the room. On a deeper level, the pronoun “it” suggests a non-human subject, as if the voice within room belonged to some kind of inhuman character.