Asa Spencer was probably born in Connecticut, United States,
around 1800. Again probably, he learned the art of engraving from Gideon Fairman,
and started working for Murray, Draper, Fairman & Co in 1815.
While it was not his invention as such, Spencer is mainly
remembered for developing geometric lathe printing, the art of printing
colourless lines. This would be used most frequently in banknote designs, but
it can also be found in the few examples of frames Spencer engraved for the
1851 definitive set of the United States.
Asa Spencer passed away in England, in 1853.
You will find Asa Spencer's database HERE.