The Scottish twin sisters Agnes Lewis (1843–1926) and Margaret Gibson (1843–1920) between them spoke modern Greek, Arabic, Hebrew, Persian and Syriac, and were pioneering biblical scholars and explorers at a time when women rarely ventured to foreign lands. The sisters made several journeys to the Monastery of St Catherine on Mount Sinai, discovering ancient biblical manuscripts, and their first two visits there were described in the 1893 publication How the Codex was Found (also available in this series). Lewis' In the Shadow of Sinai of 1898 was composed as a sequel to this work, dealing with the third and fourth journeys to Sinai, in 1895 and 1897. She gives a vivid account of the practicalities of desert travelling, as well as the excitement of the sisters and their academic colleagues as they recognised the significance of their discoveries in the monastic library.