A second hand has endorsed the MS as ‘No.48’ in the upper left-hand corner of p.94. The same hand has also added a bibliographical reference to the bottom of p.94. A third hand has added a provenance note to the bottom of p.94 that suggests that the copy is in the hand of a copyist of Panckoucke. The name ‘Descartes’ has been underlined on l.7 of the letter.