As used in statutes providing for taxes on the circulation of hanks, this term includes all currency or circulating notes or bills, or certificates or bills intended to circulate as money. U. S. v. White (C. C.) 19 Fed. 723; IT. S. v. Wilson, 106 U. S. 620, 2 Sup. Ct. 85, 27 L. Ed. 310. Circulating’ medium. This term is more comprehensive than the term “money,” as it is the medium of exchanges, or purchases and sales, whether it be gold or silver coin or any other article.