Task: Question Generation
Input (English): Passage: In the late 1830s, when much of the Old West was still Mexican territory, four people are traveling through the deserts, north of Texas and a three-day ride from Santa Fe.
One the Scalphunter, who says his trade is being a "buffaler" (buffalo hide trader). He is in search of gold. The others are a former ship Captain, also in search of the gold; the Woman from England, a former chambermaid who, in exchange for ship's passage to America, has signed an agreement to serve the Captain for five years as an indentured servant; and Mr. Rainbow, a former soldier who killed Indians.
The Captain sets out to find some of Montezuma's gold, risking danger from both the Native Indians and Mexican soldiers. The woman wants to get out of her contract with the Captain and go to New Orleans. She asks Mr. Rainbow to take her there, but he turns her down.
The Scalphunter wants half of the Captain's gold, and tags along with his men. Mr. Rainbow sets out across the desert through the Viaje de la Muerte, the Journey of Death.
Output (English): What does the nickname for the trade of the man searching for gold actually refer to?