Horner

Plaintiff and defendants occupied separate parts of the same building, defendants conducting a garage business in their portion. A fire started in the portion occupied by defendants, causing a fire loss to plaintiffs. The action has been tried twice. Defendants prevailed at the first trial, but a new trial was granted and at the second trial a jury returned a verdict for plaintiff. Judgment was entered thereon, defendants’ motion for a new trial was denied, and defendants appeal.

In support of their appeal, defendants urge insufficiency of the evidence to establish negligence, improper and prejudicial reception of inadmissible evidence, and improper and prejudicial instruction of the jury on the subject of res ipsa loquitur. They present 47 alleged errors occurring during the trial, most of them relating to the admission of improper expert opinions as to the cause of the fire.

It was plaintiff’s theory that the fire which started at about 2:30 a.m., resulted from the ignition of some kind of fuel by some “source of ignition,” allegedly the pilot or burner, or both, of a gas heater located in defendants’ office which adjoined the garage in which a number of vehicles were…