Final answer:
The provided text does not mention Bobby Kelton or the specific trick played on him by Vern Autry and Jim Cameron (or Les Haserat). The narrative focuses on other characters and themes related to the Wild West, such as horse racing and confrontations with adversaries.
Step-by-step explanation:
The question relates to the tricks played on Bobby Kelton by Vern Autry and Jim Cameron (or Les Haserat) in a narrative context. Unfortunately, the provided excerpts from what appears to be a Western novel do not contain any specific information about a character named Bobby Kelton or a trick played on him by Vern Autry and Jim Cameron (or Les Haserat). Instead, the excerpts focus on characters like Venters, the Masked Rider, Jerry Card, and the situations involving horse races, rustlers, and the handling of Jane Withersteen's racers. The narrative seems to be concerned with the themes of deception, courage, and confrontation in a Wild West setting, as exemplified by feats such as riding renowned horses and facing adversaries directly.