The papers of the Italian natural philosopher and electrician, Giambatista Beccaria (1716-1781) contain letters to Benjamin Franklin, Joseph Banks, Laura Bassi, Gian Francesco Cigna, and others on a variety of scientific topics, including atmospheric and terrestrial electricity, the aurora borealis, earthquakes, meteorology, and phosphorescence. In addition to Beccaria's epistolary essays, the collection includes several journals of meteorological observations and notes for Giovanni Eandi's biography of Beccaria.

This collection is comprised of materials from seven repositories and includes correspondence from Banks' colleagues and explorers, such as John Hope, Josiah Wedgwood, Georg Forster, and Captain William Bligh; records of expenses for voyages and journeys; and journals kept during voyages to New Foundland and Labrador (1766) and around the world with Captain James Cook (1768-1771). Topics include botany and horticulture, marine life, and collecting specimens.

Though the Miscellaneous Manuscripts collection is composed of items that do not fall readily into any other existing collection, the two dominant intellectual areas represented in the collection are Early American History and History of Science.