The development of modern cardiopulmonary resuscitation (CPR) is an exciting and surprising history to modern health professionals who rarely are aware of how new CPR really is. Artificial respiration began in the 16th century with Vesalius's work on living animals; progressed with the rise and fall of mouth-to-mouth, manual, and positive pressure ventilation methods of the 18th and 19th centuries; and culminated in 1958 with demonstration of the superiority of the mouth-to-mouth technique. Cardiac massage began in 1874, with the open chest method gaining ascendancy until the 1960 demonstration of the equality and greater ease of closed chest cardiac massage. Electrical defibrillation may have begun in 1775, but was not proven successful in animals internally until 1899. The technique was applied to man internally in 1947 and externally in 1956. The simultaneous use of all these modern CPR methods dates back only 20 years.