[A] “United States Notes. A History of the Various Issues of the Paper Money of the United States.” Chas. Scribner’s Sons, New York, third edition, 1888, pp. 16, 33, 43, 117, 216.

[B] March 18, 1869. An Act was passed in which the United States “solemnly pledges its faith to make provision at the earliest possible period for the redemption of United States notes in coin.”

Quotation from Act of Congress, approved January 14, 1875:

“And on and after the first day of January, Anno Domini eighteen hundred and seventy-nine, the Secretary of the Treasury shall redeem, in coin of the United States legal-tender notes, then outstanding, on their presentation for redemption at the office of the Assistant Treasurer of the United States in the City of New York, in sums of not less than fifty dollars. And to enable the Secretary of the Treasury to prepare and provide for the redemption in this Act authorized or required, he is authorized to use any surplus revenues, from time to time, in the Treasury not otherwise appropriated, and to issue, sell, and dispose of, at not less than par, in coin, either of the description of bonds of the United States described in the Act of Congress approved July fourteenth, eighteen hundred and seventy, entitled ‘An Act to Authorize the Re-Funding of the National Debt,’ with like qualities, privileges, and exemptions to the extent necessary to carry this Act into full effect, and to use the proceeds thereof for the purpose aforesaid.”

An Act to provide for the resumption of specie payments, approved January, 14, 1875.

Extract from Section 12, Act of July 12, 1882:

“That the Secretary of the Treasury shall suspend the issue of such gold certificates whenever the amount of gold coin and gold bullion in the Treasury reserved for the redemption of the United States notes falls below $100,000,000.”

Act approved July 12, 1882.

[C] A Plea for the Constitution. George Bancroft. Harper & Brothers. 1886.