Reid (P) was permitted by a landowner to graze certain cows on the landowner's property adjacent to train tracks. One of P's cows was struck by one of San Pedro's (D) trains and killed. The cow could have gained access to the tracks either by going through a portion of the fence negligently left unrepaired by D or by going through a gate which could have been negligently left open by P. D provided the gates for the convenience of the landowner. There was no direct evidence as to the cause of the accident. It was not even contended at trial that D left the gate open. The only solid evidence was that the animal was killed in the immediate vicinity of the open gate but one mile from the portion of the fence that was downed. There was no direct evidence to show which passage the animal used nor was there any evidence that the train was operated negligently. The jury gave the verdict to P. D appealed.