– The double dagger was used in reprints of vol. I and II to designate additions or corrections in later print runs. (Not used in Vol. III) These now may now be accessed online:
Dates: I have followed the conventions used by the University of California Press on the volumes of
Mark Twain’s Letters, except I offer the day of the week, which in some cases is helpful. To wit:
October 5 Thursday – Sources indicate this is a confirmed date, or a deduced date from events or other evidence. Firm dates come before conjectured or circa dates and date ranges.
October 3? Tuesday –
The question mark indicates a conjecture of October 3. Conjecture dates are listed separately following firm dates.
June 24–29 Saturday –
A span of dates joined by a dash indicates a less specific conjecture: the date or dates of composition are thought to fall within this span. Day of the week is ascribed to the last date in the span. The last date in a period is noted by its day of the week. Such entries are listed separately.
June 24 to 29 Saturday – Not a conjecture, but an assertion that some event ran from June 24 through June 29. Such date ranges are listed separately.
May 2 and 3 Friday –
Not a conjecture, but an assertion that the event or activity occurred at least in part on both days. Such inclusive dates are listed separately.
May 1 Friday ca. –
A conjecture of circa a date, month, year or season. Similar to May 1st? but with less specificity. May also be specified as “on or before,” or “on or after.” Circa dates are listed separately.
Items for which only a month is known, or for magazine-type publications issued for a given month.
Items for which a year is known, but not a month or date.
Note: Dates are arranged in order; spans of dates and single dates are sorted by the first date in a span. Conjectured dates are usually separate from known or consensus dates. Thus there are separate entries for May 1 Friday, and May 1? Friday ; May 17 Thursday would follow May 12–20 Sunday. Occasionally entries are labeled “Mid-month” or “End of Month” or “Early Spring,” etc. Confirmed dates are listed first.