124 N.W.2d 514 MARIE BARTELS, appellant, v. CAIR-DEM, INCORPORATED, appellee. No. 51083.Supreme Court of Iowa. November 12, 1963. EVIDENCE: Circumstantial — proof. An issue may be proven by 1 circumstantial evidence, but this evidence must be such as to make the theory of causation reasonably probable, not merely possible, and more probable than any other […]