Ivan Puluj, a physicist born in Hrymailiv (Ukraine, then Austro-Hungarian Empire), builds between 1881 and 1889 a series of gas-discharge tubes that produce ionizing radiation capable of passing through tissue and projecting images of bones onto photographic plates. In 1896, weeks after Röntgen announced the discovery of X-rays (November 1895), Puluj published photographs of skeletons and hands made with his own tube, and claimed to have obtained similar images years earlier without publishing them. Röntgen discovered the phenomenon without knowing that tubes capable of producing it already existed; Puluj built functionally equivalent tubes without identifying the phenomenon as a specific form of radiation. His instrumental contributions predate Röntgen's but were not published systematically.