Ultrasound was originally developed in WWII to detect enemy submarines. After the war in 1955, a surgeon in Glasgow named Ian Donald, began to experiment with it for medical uses. Using beefsteaks as the “control” subject, he scanned the abdominal tumors he had removed from his patients and found that different tissues gave different patterns of sound wave echo. He quickly realized the potential of ultrasound for examining a growing baby in utero.