arrangements began to formalize and become permanent. During the American Civil War, Jonathan Letterman devised a system of mobile field hospitals employing the first uses of the principles of triage. After returning home, some veterans began to attempt to apply what had they had seen on the battlefield to their own communities, and commenced the creation of volunteer life-saving squads and ambulance corps. These early developments in formalized ambulance services were decided at local levels, and this led to services being provided by diverse operators such as the local hospital, police, fire brigade, or even funeral directors who often possessed the only local transport allowing a passenger to lie down. In most cases these ambulances were operated by drivers and attendants with little or no medical training, and it was some time before formal training began to appear in some units. An early example was the members of the Toronto Police Ambulance Service receiving a mandatory five days of training from St. John as early as 1889. Prior to World War I motorized ambulances started to be developed, but once they proved their effectiveness on the battlefield during the war the concept spread rapidly to civilian systems. In terms of advanced skills, once again the military led the way. During World War II and the Korean War battlefield medics administered painkilling narcotics by injection in emergency situations, and pharmacists' mates on warships were permitted to do even more without the guidance of a physician. The Korean War also marked the first widespread use of helicopters to evacuate the wounded from forward positions to medical units, leading to the rise of the term "medevac". These innovations would not find their way into the civilian sphere for nearly twenty more years. Prehospital emergency medical care By the early 1960s experiments in improving medical care had begun in some civilian centres. One early experiment involved the provision of pre-hospital cardiac care by physicians in Belfast, Northern Ireland, in 1966. This was repeated in Toronto, Canada in 1968 using a single ambulance called Cardiac One, which was staffed by a regular ambulance crew, along with a hospital intern to perform the advanced procedures. While both of these experiments had certain levels of success, the technology had not yet reached a sufficiently advanced level to be fully effective; for example, the Toronto portable defibrillator and heart monitor was powered by lead-acid car batteries, and weighed