The publisher's decision to date the
General Index 1820 contributes to the confusion over the
QR's real publication dates and the dates that
appear on the journal's title pages (concerning which, see
this website's essay on the
topic). The first part of the General Index was
published in March 1820 and the second part in June of that
year. As the year on the title page for Volume 19 is 1818
and that for Volume 21 is 1819, the sequence of the
QR's title page dates was therefore corrupted.