As a matter of convenience to the public, the United States Government has authorized the Secretary of the Treasury to receive deposits of gold coin and bullion in sums not less than $20, and issue certificates therefor in denominations not less than $10. Inasmuch as these certificates are receipts for gold, they are redeemable in gold coin by the Treasurer and by all Assistant Treasurers of the United States. The law provides that "the Secretary of the Treasury shall suspend the issue of gold certificates whenever the amount of gold coin and gold bullion in the Treasury, reserved for the redemption of United States notes, falls below one hundred millions of dollars." The Secretary is also empowered, in his discretion, to suspend such issue whenever and so long as the aggregate amount of United States notes and silver certificates in the general fund of the Treasury shall exceed $60,000,000; he must also see that at least one-fourth of all certificates outstanding shall be in denominations of $50 or less.

On Dec. 1, 1916, the face value of these certificates outstanding amounted to $1,573,376,719.

They were not legal tender, but receivable for customs, principal and interest in gold, yet, since the Act of March 14, 1900, provided that the Secretary of the Treasury shall maintain all forms of United States money at a parity of value with gold, it seems that all United States bonds would do for the purpose.

1 Prescott, in his " Conquest of Mexico," speaks of the ancient Aztecs using gold " cast into bars " as part of the regular tribute of the Southern provinces of the empire.

Act of March 14, 1900, as amended March 4, 1907. taxes, and all public dues. They may be used as part of a national bank's "reserve."