The posse heads to Salt Lake City, and are surprised that the trip is completely uneventful. There is considerable discussion on the way about what they should do when they get there, especially knowing when they should run away. Tobey is especially worried about being shot for being dead. And should they have a plan for kidnapping Elder Tanner back? How will they know if he wants to be kidnapped from the Mormons? Eventually Cady points out that they can just kidnap him and throw him back if that turns out to be the wrong thing, and strangely everyone goes along with that plan.
In Salt Lake, they marvel at the electric lights. Dr. Vorpwhistle is also interested in the way soot seems not to accumulate on the houses of the faithful. Elder Tanner returns to the bosom of his family - he's the eldest son of Myron Tanner and his first wife Mary Jane (the other two wives being Mary Kate and Kathy Jane). After an uncomfortable while in which Things Aren't Discussed, he's called into the study to tell his father what happened. Then he's shut in his room while his father figures out what to do, and after a while of that is dragged off by serious men to a cell under the Temple. On the way out, his father asks him which of his companions is the most likely to give supporting testimony, and he says "Cady Hearst".
Meanwhile, Cady has gone shopping, purchasing new clothes for herself and Tobey (Tobey refuses to leave the hotel, deciding to stay out of trouble). Then she goes to a bookstore in town that has several old copies of Hoyle's - apparently they are a collector's item. She buys all of them, spending a couple hundred dollars in the process. She also gets to see, but not touch, a copy of "Rascals, Varmits, and Critters", a publication of the Explorer's Society which has been mostly confiscated by the Texas Rangers. Though that costs $500, it is later purchased by the party and Dr. Vorpwhistle's expense account in collaboration. Dr. Vorpwhistle also spends time at the local Engineering College, which treats him well due to his impeccable credentials.
Later that night as Cady and Tobey sit at the quiet minder's tables in The Monkey-wrench, a science-bar, a Mormon gentleman approaches and introduces himself as Myron Tanner, Joseph Tanner's father. He wants to know if the crazy story his son has been giving him is true. Cady and Tobey give mostly the same story, though with some emphasis on all the cool things that Joseph has done along the way. Myron listens and thanks them.
The next day, Joseph is brought before a board of senior Mormons, including a black-clad man who reminds him of James. They listen to his story again, and Myron, who is also at the trial, backs him up on it. They deliberate some after the testimony, and decide that since the Tanner family has been known to have visions before, his behavior isn't out of line. The pagan and evil tattoos, though, have to go. They'll cut off his arm tomorrow, meanwhile he is let free. He goes to tell his companions.
"I'm getting my arm taken off tomorrow, which is really much better than what I've been fearing." - Joseph
Cady accepts the invitation to dinner at the Tanner house, and acts as a completely proper lady the whole time. Joseph's mother keeps giving him significant looks, and later corners him to tell him that after what he's been through and with only one arm he's not the greatest catch. Cady, alone out of all womanhood, will at least understand what he's been through. He shouldn't let her escape! Joseph refrains from telling his mother more about Cady.
The next day everyone goes to watch the operation, which is being done in the college's operating theater. They use a new self-cauterizing bone saw. As well as the posse, the armed Mormon who reminded Joseph of James is also in attendance, actually down by the operating table.
Which is just as well, since as soon as it is cut off the arm grabs the doctor by the throat and starts strangling him. Tobey leaps down and cuts it off at the wrist, and then the dangerous Mormon scoops it and the hand up in a cloth and takes them to the Temple to be burned in holy fire. Joseph is bandaged up by Tobey and then again by the doctor once he recovers from the shock.
Tobey's thoughts after studying the pamphlet: