It was for the district court to determine the ultimate issue of fact as to whether or not the payment was a gift or compensation. It found as a fact that the payment was compensation. Froehlinger v. United States, 217 F.Supp. 13 (D.C.Md. 1963). That finding of ultimate fact is binding upon us. Commissioner v. Du-berstein, 363 U.S. 278, 80 S.Ct. 1190, 4 L.Ed.2d 1218 (1960); Poyner v. C. I. R., 301 F.2d 287 (4th Cir. 1962).

Affirmed.