Aetna Casualty & Surety Company and Others

This case is making its second visit to this court. It involves the question whether a steel storage tank containing grain exploded within the meaning of the term ""explosion"" in an insurance policy. In the first trial the jury found there was an explosion but on appeal we reversed and granted a new trial because of error in instructing the jury on the question of what constitutes an explosion. Aetna Casualty & Surety Co. v. Osborne-McMillan Elevator Co. (1965), 26 Wis. 2d 292, 132 N.W.2d 510. Upon the retrial, the jury again found the grain elevator exploded and judgment was entered upon the verdict for $483,320.89 damages together with $91,884.43 interest and $19,705.12 costs, for a total of $594,910.44. A year after the second trial the Minnesota supreme court decided an explosion case which the appellants claim is determinative of the Minnesota law which is applicable to this case. Again before us are questions relating to what constitutes an explosion as the term is used in an insurance policy, the sufficiency of the evidence, and the correctness of rulings on motions and of the instructions to the jury. The physical facts on this appeal are essentially the same as on the first and most of them are set forth in our previous opinion but some must be repeated to give a background understanding of the present issues. This action was commenced for declaratory relief by 44 appellant insurance companies (the insurance companies) to determine their liability under insurance policies for a loss suffered by the defendant-respondent Osborne-McMillan Elevator Company (the elevator company). One policy insured the buildings and the equipment and the other policy insured contents against various perils including explosion under an extended-coverage endorsement.