If it be thought that, at most, the legislative purpose as expressed by the words employed is ambiguous, still the holding must be adverse to appellant because doubt in such cases is invariably resolved in favor of the taxpayer. McDaniel v. Burkett, 120 Ark. 295, 179 S.W. 491; Wiseman v. Arkansas Utilities Co., 191 Ark. 854, 88 S.W.2d 81; Hardin, Commissioner v. Smith Couch Bedding Co., 202 Ark. 814, 152 S.W.2d 1015. Affirmed.