David Gregory appears to have indexed Folio B (along with Folio C and Quarto A) in Oxford in late 1699 or early 1700, when he was gradually completing his magnum opus, the Astronomiae. His editorial rationale for these apparently random collections is not clear. The descriptions on the index represent a scattering of items, chiefly notes and papers of his own in mathematics and astronomy, and of others, including Apollonius of Perga (262 BC-190 BC), Johannes Kepler (1571-1630), Jean Bernoulli (1667-1748), and Jean Domenique Cassini (1625-1712), with correspondence among Gottfried Willhelm Leibniz (1646-1716), Cassini, Isaac Newton (1642-1727), his father, David Gregory Sr., and his uncle, James Gregorie (1638-1675). Non-scientific professional papers that he meant to include cover, among other things, the 1690 visitation, Scottish ecclesiastical matters, and business and agriculture. As well, he included a pair of curiosities: 'figures of Louis XIV' and some poems, 'good, bad, and burlesque'. Their dates tend toward his later professional life, from the visitation onward. Because paleographic evidence suggests that these pages were not stored carefully, Gregory may have meant them to be more a stack of back files than an orderly documentary record of anything.