Hamilton came into the case through Frank Sibley, who happened to meet him while riding on the train from Portland, Maine, to Boston. Hamilton, an authoritative little man with a convincing air, told Sibley that if he had been a witness at Dedham he could have proved quickly and conclusively whether or not Sacco’s pistol had fired the mortal bullet. Once back in Boston Sibley recommended Hamilton enthusiastically to Moore. The lawyer immediately wrote Hamilton to ask what he would charge for coming to Boston. Without bothering to reply, Hamilton confidently took the next train. In their first interview Moore told Hamilton he was vitally concerned in learning the answers to four fundamental questions: Had the hammer of the Vanzetti revolver been replaced by a new hammer? Were one or more of the shells that Fraher had picked up fired in the Sacco pistol? Had Bullet III been fired from the Sacco pistol? Was the mortal bullet discharged from a cartridge of the same date of manufacture as any of the cartridges found on Sacco when he was arrested? Hamilton agreed to make the investigation and determine the four answers. Hamilton was an unlucky choice. Moore did not suspect that his doctorate was self-awarded. By trade a druggist and concocter of patent medicines in Auburn, New York, Hamilton had developed expertness as a second career, advertising himself as a “micro-chemical investigator.” His avocation became his calling. In 1908, in a publicity pamphlet entitled “That Man from Auburn,” he described himself as a qualified expert in chemistry, microscopy, handwriting, ink analysis, typewriting, photography, fingerprints, toxicology, gunshot wounds, guns and cartridges, bullet identification, gunpowder, nitroglycerine, dynamite, high explosives, blood and other stains, causes of death, embalming, and anatomy. Unknown to Moore, he had earlier written to Judge Thayer claiming that he knew a method of examining the Sacco-Vanzetti ballistics exhibit that would reveal the truth. He had received no reply. Men who had worked with Hamilton in the past did not recommend him. The Auburn coroner said that his reputation for truth was bad. The assistant district attorney of Monroe County considered him “a professional expert ... whose testimony should not be accepted in any court of record, and should receive no credence at the hands of a judge or jury.”