This Convention represents the fourth version of the Geneva Convention on the wounded and sick after those adopted in 1864, 1906 and 1929. The fundamental principles as well as the division into chapters remained the same as in the preceding version with the exception of the new introductory chapter on general provisions. Changes were made especially in Chapter IV (personnel). Hitherto, medical personnel and chaplains falling into enemy hands had to be immediately repatriated. The 1949 Convention, taking account of changed conditions of warfare, provides that they may in certain circumstances be retained to care for prisoners of war. The provisions on medical equipment were correspondingly altered. In the chapter on medical transports it was provided that medical aircraft may in certain circumstances fly over neutral territory. Some clarifications were made as regards the article on the use of the emblem (Article 44).