Sorry to hear about your bad cold, tsuwm. Good chicken soup, as someone suggested on another thread, and plenty of rest will help more than anything.

Single source--Mrs. B? Well, not really, since she would count as at least two sources in every case. She ostensibly took some of her very rare words from one source and then she published her lexicon, so that would make two sources.

We've had some oddball words here on AWAD that have sometimes confounded us in trying to track them down. On those occasions, you have often saved us with the OED, but perhaps these words have been in other dictionaries, too--just not in the ones included on Onelook, for instance.

I do wonder about your comment that Mrs. B sometimes exaggerates. I would guess that she at least was honest in what she included in that she included words that appeared in at least one lexicon, even those of lexicographers who may have been less than rigorous in application of their own sources. But Mrs. B's job wasn't to present a book of bona fide, standard entries; instead, it was to present a book of entries--even 'preposterous' ones--that had appeared in at least one lexicon. What an interesting hobby she had there!

However, it's a real pity that she--or they--didn't footnote some of the more obscure references.