There are several parts to this Musing:
PROLOGUE: the discovery
PART I: the volume at the Lilly Library which is accompanied by a page about emendations in a different hand, and a page about reworked G clefs
PART II: Marc-Antoine Charpentier the Theorist
PART III: Marc-Antoine Charpentier as a drafter of composition manuals, wherein you will find images of each page of manuscript "XLI" for personal study
PART IV: Proof and Conclusion
See also my complementary Musings about this manuscript and its broader context:
Does anyone recognize the hand of the person who owned the Charpentier autograph treatise, circa 1710?
Click on this small picture, for an enlarged image of a page from the manuscript treatise called Traité d'accompagnement, As the final section of my presentation of manuscript "XLI" shows, this unidentified person knew Marc-Antoine Charpentier personally and exchanged ideas with him, probably during the 1690s.
It is titled:
"A study of Traité d'accompagnement et de composition, an anonymous French accompaniment treatise of ca. 1700 in Indiana University Lilly Library," by Carla Williams (2012)
On May 9, 2013, she informed me: "For those interested in gaining access to my thesis, it is currently available through Interlibrary Loan from the Cook Music Library. More information may be found in the catalog (IUCAT) record: http://new.iucat.iu.edu/catalog/12124865 . Also, I am currently putting together a book prospectus for IU Press in order to publish an edition of the manuscript. Hopefully that will soon be moving forward."
Earlier she briefly discussed the Traité d'accompagnement
and Charpentier's six leaves, in Journal of Seventeenth-Century
Music, vol. 15, no. 1: