[78-L] Vocalion information needed

[Thomas Stern]

Need to know what the following numbers are:
  Vocalion 21005
  C7799
  C7837
  VO 1073
  VO 1074

These numbers are referenced as issues of Roland Hayes recordings from
the 1922/3 London sessions,
however the number 21005 (which is given in the NEW WORLD LP notes) refers
to titles which were issued on 21002 - I suspect this is a typo, but
would like confirmation.

The others might be release or matrix numbers - I do not find pairs of titles
referencing the same numbers.  So these may be single sided (if such were
issued), paired with another performer, or pseudo matrix numbers.

Concerning  Vocalion matrix numbers - I have one instance
where a UK issue and US issue have the same basic number, but
the UK version suffixed with an X (02874X/02874 By an By).
Anyone know what this indicates? (alternate take, dub, nothing?, ??).

Thanks!
Best wishes, Thomas.