A sudden and rapid combustion, causing violent expansion of the air,and accompanied by a report. The word “explosion” is variously used in ordinary speech, and is not one that admits of exact definition. Every combustion of an explosive substance, whereby other property is ignited and consumed, would not be an “explosion.” within the ordinary meaning of the term. It is not used as a synonym of “combustion.” An explosion may be described generally as a sudden and rapid combustion, causing violent expansion of the air. and accompanied by a report. But the rapidity of the combustion, the violence of the expansion, and the vehemence of the report vary in intensity as often as the occurrences multiply. Hence an explosion is an idea of degrees; and the true meaning of the word, in each particular case, must be settled, not by any fixed standard or accurate measurement, but by the common experience and notions of men in matters of that sort. Insurance Co. v. Foote. 22 Ohio St. 348, 10 Am. Rep. 735. And see Insurance Co. v. Dorsey, 50 Md. 81, 40 Am. Rep. 403; Mitchell v. Insurance Co., 16 App. D. C. 270; Louisville Underwriters v. Durland, 123 Ind. 544, 24 N. E. 221, 7 L. R. A. 399.