Page 126 - Charles Shreve - William H Gross United States 1847 Issue

Section Seven: Epilogue - Atier Demonetization

A. Last day of validity and first day of demonetization

The Act of Congress that established new postal rates effective July 1, 1851, provided that the 1847 stamp issue would
cease to be valid on that date. They could be exchanged for cash or stamps of the 1851 issue until October 1, 1851.

JU 30,1851 to New York, NY.
Last day of validity

JY 1, 1851 to Naugatuck, CT.
Overpaying the new 3~ rate by 2~.
One of two recorded first day of demonetization usage covers