In the 1790s , however , several of his international speculations failed and in 1798 he was declared bankrupt .
Throughout the 1770s and 1780s , Green 's engraving practice flourished .
In the 1790s , however , several of Green 's international speculations failed and in 1798 he was declared bankrupt .
Throughout the 1770s and 1780s , Green 's engraving practice flourished .