Fī ʻilal al-jihāz al-tanaffusī (On the diseases of the respiratory system) is a translation from the French into Arabic of Hippolyte de Brun's Traité des Maladies de l'Appareil Respiratoire.Hippolyte de Brun (1855−1931) was professor of medicine at the Université Saint-Joseph, a Catholic university in Beirut founded by the Jesuits in 1875. He was also a physician at the French hospital in Beirut, and chair of clinical medicine from 1885 to 1914 and 1919 to 1926. The translator of this work, Khayr Allāh Faraj Ṣufayr, was a graduate of the same university and was a muʻāwin (extern) at the French hospital. In the preface to his translation, Ṣufayr praises—as a matter of formality—the progressive policies of the Ottoman Sultan Abdulhamid II (reigned 1876−1909), identifying them as the impetus to the creation of his work. He also emphasizes the difficulty of translating modern medical terminology into Arabic. The translator describes the book as having been undertaken under the supervision of its original author, de Brun, and as consisting of four chapters. The table of contents of the translated work, however, appears to reveal a basic division into five chapters: on diseases of the nasal cavity, the throat, the bronchi, the lungs, and the pleural cavity. The work includes a glossary of medical terms and the foreword to de Brun's original work. It was published at the printing house at UniversitéSaint-Joseph in Beirut in 1888.