gift the latest Mk IV flaw detector, which was subsequently forwarded to Glasgow Central station from the Barkingside Labs location for delivery to Brown. Rankin also spoke to the three directors at the company who decided to vote £500, a considerable sum in those days to support experiments. The new machine considerably improved on the older machine with the difference being described as "chalk and cheese" by Donald. The Mk IV was a double transducer probe machine. At the same time, Brown found a Cossor oscilloscope camera that allowed images to be recorded on 35mm film. For Donald, the camera was particularly significant, as it enabled a record to be kept, an archive of images to be created that could be printed in published works. Donald set about establishing a framework of use for the device, how it could be used, what the information on the screen meant. In 1956, the obstetrician John MacVicar was appointed as a registrar at the Western Infirmary and joined the team, By 1956 Donald and MacVicar became proficient with the machine after scanning 250 patients. For most of that period, they had tried to determine why particular scans produced a particular image. They discovered that if there was fluid in the abdomen, e.g. an ovarian cyst, there would be a clear gap in the image until the ultrasound reached the other side of the cyst. They then tried to distinguish between different ascites by matching images to particular type of ascites. They also investigated the shapes of images in the presence of uterine fibroids. Around that time, Edward Johnson Wayne of the Department of Medicine at the Western Infirmary had heard of Donald's research and was keen on a demonstration of the technique. Wayne invited Donald to use his detector on a woman who was dying from supposed stomach cancer. She was vomiting and losing weight rapidly; a barium x-ray had confirmed the diagnosis. Donald agreed with the diagnosis of ascites and applied the probe. They discovered that while they could use abdominal palpation to differentiate masses, Donald was using machinery to achieve the same result. MacVicar not knowing the background of the case, commented, "It looks like a cyst." Donald had to apologise to his colleagues, as the diagnosis of a cyst was preposterous. After a meeting to discuss the case, it was agreed that a laparotomy would be performed by Donald. To