On April 15, 1790, Congress instructed the Secretary of the Treasury, Alexander Hamilton, to prepare and report a proper plan for the establishment of a national mint. This was done at the ensuing session of Congress. The act was framed and passed finally March 26, 1792, and received the approval of President George Washington April 2, 1792. A lot of ground was purchased on Seventh Street near Arch, and appropriations were made for erecting the necessary buildings. An old stillhouse, which stood on the lot, had first to be removed. In an account book of that time we find an entry on July 31, 1792, of the sale of some old material from the stillhouse for seven shillings and sixpence, which Mr. Rittenhouse directed “should be laid out for punch in laying the foundation stone.” David Rittenhouse was the first Director of the Mint, April 14, 1792, until his health compelled him to resign in June, 1795. This building for the United States Mint in Philadelphia was the first structure erected in America for public use under authority of the Federal Government. It was a brick building, the cornerstone of which was laid by David Rittenhouse July 31, 1792. In the following October operations were commenced by the coinage of the silver half dimes. President Washington mentions this first coinage in his address to Congress, November 6, 1792, as follows: “There has been a small beginning in the coinage of half dimes, the want of small coins in circulation calling the first attention to them.” The original purchase of metal for coinage was six pounds of old copper at one shilling and three pence per pound, which was coined and delivered to the Treasurer in 1793. The first deposit of silver bullion was made July 18, 1794, by the Bank of Maryland. This consisted of coins of France amounting to $80,715.73½. The first return of silver coins to the Treasurer was made on October 15, 1794. The first deposit of gold bullion was made by Moses Brown, a Boston merchant, on February 12, 1795, and paid for in silver coins. The first gold coins turned into the Treasury were 744 half eagles, on July 31, 1795. Eagles were first delivered September 22, when 400 were delivered. There were four different currencies or rates, in different parts of the Union, and a consequent perplexity, until the passage of the law which regulated the coins of the United States. The present system of coins is formed upon the principles laid down in the resolution of 1786, by which Congress determined the denominations should be dollars (the dollar being the unit), dimes or tenths, cents or hundredths, and mills or thousandths of a dollar. Nothing could be more simple or convenient than this decimal sub-division. The terms are proper because they express the proportions which they are intended to designate. The dollar was wisely chosen, as it corresponded with the Spanish coin, with which the colonists had long been familiar.