In Seward's diary entry Dr. Van Helsing proves to Dr. John Seward, Quincy Morris and Lord Arthur Godalming that their beloved Lucy Westenra has risen from the dead as a vampire. Van Helsing has already brought Seward to Lucy's coffin twice without completely convincing him of the fact. Now, he has brought all three men to the tomb.
As Seward and the other two men wait and watch Van Helsing prepare the tomb for Lucy's rising, Seward describes the atmosphere:
Never did tombs look so ghastly white; never did cypress or yew, or juniper so seem the embodiment of funereal gloom; never did tree or grass rustle so ominously; never did bough creak so mysteriously; and never did the far-away howling of dogs send such a woeful presage through the night. (Stoker)
Seward's ominous description of his surroundings as he waits to witness the unimaginable horror of Lucy as a vampire has warped his view of the natural world into something that's unnatural as plants and domestic animals become creepy and foreboding.
Stoker captures this ability of the human mind so well here. I've never waited for anyone to rise from their coffin as a vampire, but I've definitely had the experience where my mood has unnaturally altered my perception of normally innocuous things that we barely notice under normal circumstances. Has this ever happened to you?