Section 4 of the Act of June 20, 1874, Entitled “an Act Fixing the

amount of United States notes providing for a redistribution of National bank currency and for other purposes,” shall be required to give thirty days’ notice to the Controller of the Currency of its intention to deposit lawful money and withdraw its circulating notes; provided that not more than five million of dollars of lawful money shall be deposited during any calendar month for this purpose; and provided further, that the provisions of this section shall not apply to bonds called for redemption by the Secretary of the Treasury.