PROLOGUE TO THE SIXTH STORYOn the last occasion when I made a lengthened stay in London, my wife and I were surprised and amused one morning by the receipt of the following note, addressed to me in a small, crabbed, foreign-looking handwriting.
"Professor Tizzi presents amiable compliments to Mr. Kerby, the artist, and is desirous of having his portrait done, to be engraved from, and placed at the beginning of the voluminous work on 'The Vital Principle; or, Invisible Essence of Life,' which the Professor is now preparing for the press—and posterity.
"The Professor will give five pounds; and will look upon his face with satisfaction, as an object perpetuated for public contemplation at a reasonable rate, if Mr. Kerby will accept the sum just mentioned.
"In regard to the Professor's abil
