How does Stevenson depict urban London as a somber and threatening place? (Chapters 1 & 2)

Check out this quote from Chapter 2. Utterson seems to be having a dream sequence yet it highlights the sort of place London was. You will see the dark rather creepy London that the author portrays,

"Six o'clock stuck on the bells of the church that was so conveniently near to Mr. Utterson's dwelling, and still he was digging at the problem. Hitherto it had touched him on the intellectual side alone; but now his imagination also was engaged, or rather enslaved; and as he lay and tossed in the gross darkness of the night and the curtained room, Mr. Enfield's tale went by before his mind in a scroll of lighted pictures. He would be aware of the great field of lamps of a nocturnal city; then of the figure of a man walking swiftly; then of a child running from the doctor's; and then these met, and that human Juggernaut trod the child down and passed on regardless of her screams. Or else he would see a room in a rich house, where his friend lay asleep, dreaming and smiling at his dreams; and then the door of that room would be opened, the curtains of the bed plucked apart, the sleeper recalled, and lo! there would stand by his side a figure to whom power was given, and even at that dead hour, he must rise and do its bidding. The figure in these two phases haunted the lawyer all night; and if at any time he dozed over, it was but to see it glide more stealthily through sleeping houses, or move the more swiftly and still the more swiftly, even to dizziness, through wider labyrinths of lamplighted city, and at every street corner crush a child and leave her screaming. And still the figure had no face by which he might know it; even in his dreams, it had no face, or one that baffled him and melted..."

That dude Aslyn up there said like way to much. If your looking for an answer for your homework, which probobly says something like "How does the Author depict London as a Somber and threatining place? Provide at leat two examples from the text." the answer is, at least this is what i wrote, one, by the ugly door, and two, by the Juggernaut