From Orb to Speaking Phantom?

Reports of the appearance of a phantom called Bien Boa are some of the strangest stories in the literature of the paranormal.  One such account by Professor Charles Richet can be read beginning on page 269 of Volume 2 of the Annals of Psychical Research.  On page 179 of Volume 3 of the Annals of Psychical Research, we read this about this Bien Boa:

"This witness had also been present at the building-up of B. B. outside the cabinet in the form of a whirling white ball, from which there presently proceeded first the head and then the whole body ; he has also heard B. B. speak and give moral advice."

A similar account appears on page 416 of the same volume, which talks about a white ball that "in less than two minutes transformed itself into a materialised spirit."  (The page numbers I just gave refer to the page numbers appearing in the volume, rather than the PDF file page numbers.)