Mr. Specter. Will you continue to describe what that X-ray shows with respect to metallic fragments, if any?
Dr. Gregory. Three shadows are identified as representing metallic fragments. There are other light shadows in this film which are identified or interpreted as being artifacts.
Mr. Specter. What is the basis of distinction between that which is an artifact and that which is a real shadow of the metallic substance?
Dr. Gregory. A real shadow of metallic substance persist and be seen in other views, other X-ray copies, whereas artifacts which are produced by irregularities either in the film or film carrier will vary from one X-ray to another.
Mr. Specter. Is it your view that these other X-ray films led you to believe that those are, in fact, metallic substances?
Dr. Gregory. As a matter of fact, it is the mate to this very film, the lateral view marked "B", which shows the same three fragments in essentially the same relationship to the various levels of the forearm that leads me to believe that these do, in fact, represent metallic fragments.
Mr. Specter. Will you describe as specifically as you can what those metallic fragments are by way of size and shape, sir?
Dr. Gregory. I would identify these fragments as varying from five-tenths of a millimeter in diameter to approximately 2 millimeters in diameter, and each fragment is no more than a half millimeter in thickness. They would represent in lay terms flakes, flakes of metal.
Mr. Specter. What would your estimate be as to their weight in total?
Dr. Gregory. I would estimate that they would be weighed in micrograms which is very small amount of weight. I don't know how to reduce it to ordinary equivalents for you.