Was "Tanner" actually a doctor?  It seemed unlikely.  Medical men, even the worst of them, tended to shy away from hanky-panky contrary to their professional code.  Take that ship's surgeon, Nelson - he had quit, washed his hands of the case simply because - wait a minute!  Dr. Nelson was one man who could tell offhand whether that young fellow was the Man from Mars, without checking calluses, using trick questions, or anything.  Caxton reached for buttons, ordered his cab to ascend to parking level and hover, and immediately tried to phone Dr. Nelson, relaying through his office for the purpose since he neither knew where Dr. Nelson was, nor had with him the means to find out.  Nor did his assistant Osbert Kilgallen know where he was, either, but he did have at hand resources to find out; it was not even necessary to draw on Caxton's large account of uncollected favors in the Enclave, as the Post syndicate's file on Important Persons placed him at once in the New Mayflower.  A few minutes later Caxton was talking with him.