The Chaucer Review: An Indexed Bibliography (Vols. 1-30)

Longsworth, Robert M. "Privileged Knowledge: St. Cecilia and the Alchemist in the Canterbury Tales." 27 (1992): 87-96.
The Canon's Yeoman's Tale and the Second Nun's Tale both treat transformation. In the Canon's Yeoman's Tale alchemy is presented as fraud with only monetary consequences for the dupe. The Canon's Yeoman is careful to show the abuse of fundamental principles. In the Second Nun's Tale transformation has mortal consequences for believers, and as a result deals with a double epistemology. Believers can see what non-believers cannot. The narrator is responsible for the presentation of these two kinds of knowledge. The narrator of the Second Nun's Tale merely claims that he is reporting from a source, probably Jacobus de Voragine, whereas the narrator of the Canon's Yeoman's Tale is making a confession.