b c 1770 - d
c 1810=1833
c 1815=1833
c 1820
1826-1836
1890-1910
1815-1833
c 1815
c 1810=1815
c 1822=1826
c 1830=1840
c 1800=1840
1806 (introduction date)
1820-1833
