Among the illustrations, facing page 243, is a color plate by Roscoe's young niece Beatrix Potter. The illustration, titled "A Dream of Toasted Cheese" features a bespectacled mouse perched on a Bunsen burner reading a book, a quantity of mice amidst various laboratory equipment in the background. Initialed and dated in the print "H.B.P. Dec. 99." An early Potter illustration, predating her popular "Peter Rabbit" series of children's books, seemingly overlooked by her bibliographers and apparently the only Potter illustration in a work of non-fiction published during her lifetime. A must have for the Beatrix Potter completist.