How is suspense created in this chapter?

In chapter seven there is a lot of suspense created. At the begining, Pap is asleep and Huck is trying to get away from him, so he sneaks out in a canoe. Then Huck hears Pap wake up and he tries to get away as quickly as he can so Pap does not catch him escaping. "About twelve o'clock we turned out and went along up the bank." (Mark Twain, Ch. 7, P.42) Huck tells Pap that the noise he heard was someone else.Pap wakes up and tells Huck that if anyone comes back, to wake him up so he can kill that person.