Before June 1, 1792, postage was charged in a non-decimal terms of pennyweights and grains of silver. The federal postal act of February 20, 1792 established a decimal system of payment with 9 levels of charge dependent on miles carried. The rates remained in effect until March 2, 1799 when the 9 levels were reduced to 6 levels.The letter from New York City to Albany was charged 30c. This reflects a double weight of the 15c charged for letters traveling between 150 and 200 miles.
The New York postmark is the "clamshell" used from 1798 to 1802.
