From Prof. Oddfellow's sketchbook:
The text reads, "Each pea in a pod is engirdled by an imaginary line corresponding to the great circles of our celestial sphere. This can be verified by anyone who wishes to take the trouble."
Our piece was inspired by an illustration in
Illustrated British Ballads, Old and New, 1894. Its caption reads, "Now when they got as far as the equator, they'd nothing left but one split pea." That pea must have been split equatorially, eh?