It is real. I went looking half expecting an internet fabrication, one of those artifacts that exists mainly as a caption under a photograph of something else. The Radiendocrinator is documented, catalogued, and sitting in a museum collection in Oak Ridge, where a health physicist had to remove its radium source before he could put it on display.

The short version. In the 1920s you could buy a gold plated device roughly the size of a playing card, containing radium soaked blotter paper, packaged in an embossed leatherette case with a velvet lining. It came with a strap the manufacturer called an adapter. Men were instructed to wear the adapter like an athletic supporter, which placed the device under the scrotum, and to sleep in it.

That is the part everyone repeats, and it is true, and it is not the interesting part. The interesting part is that this was not sold as an alternative to medicine. It was sold as the consumer edition of the most exciting legitimate science of the decade.

Endocrinology in the 1920s was where the light was. Starling had named hormones in 1905. Insulin went into a dying fourteen year old in January 1922 and he got up and walked out. The idea that tiny quantities of a secreted substance could govern growth, metabolism, temperament and aging was new, correct, and nowhere near fully mapped. Into that gap walked the rejuvenators.

Eugen Steinach was nominated for the Nobel Prize in Physiology or Medicine six times between 1921 and 1938. His vasectomy variant was popular enough that his name became a verb and men were said to have been Steinached. Serge Voronoff grafted monkey testicular tissue into aging men and, at the 1923 International Congress of Surgeons in London, was applauded by an audience of several hundred surgeons. The BMJ reviewed his book without contempt.

So the pitch writes itself, and it did. American Endocrine Laboratories distributed a book with the title Scientific Rejuvenation Without Operation. The whole proposition of the Radiendocrinator was not that mainstream medicine was wrong. It was that mainstream medicine was correct, and inconvenient, and required a surgeon and a monkey. Here was the same benefit in a velvet lined box, mail order, no incision.

The name is the entire argument compressed into six syllables. Radi. Endo. Crinator. It attaches the glamour of the new physics to the glamour of the new physiology, and the customer supplies the mechanism himself.

Quackery of this grade needs a physician, and it had one. Herman H. Rubin, MD, wrote the rejuvenation books, appeared in newspaper photographs standing next to the football sized clinic model, and admitted using the device in his practice. He denied selling it or holding any interest in the company.

The denial had architecture. When Rubin prescribed the device to his own patients, he did so through Radisante Endocrine Laboratories, which called the identical product the Rubin Endocrinator. Radisante was American Endocrine Laboratories under a different name. In 1926 it became U.S. Gamma Laboratories. Three corporate identities, two product names, one device, and a doctor who could say with a straight face that he had no business interest in the company whose product he prescribed.

The medical societies of New York State and New York County were not persuaded. They expelled him in March 1924, over his commercial entanglement with patent medicines and devices. He kept publishing. The company kept selling. It manufactured its last unit in 1929 and closed in April 1930 with a paper net worth near $85,000, describing itself on the way out as a manufacturer of special machinery.

Nobody in the popular retellings does the arithmetic, so here it is, with its limits stated up front.

The only dose datum available is the surviving specimen: roughly 200 mR/hr on contact, measured with a beta gamma GM detector. That number is not an absorbed dose to tissue and should not be mistaken for one. A GM tube over responds to beta particles relative to its gamma calibration, and most of that beta energy stops in the gold, the screens, the case and the scrotal skin rather than reaching the germinal epithelium. The testes also sit centimetres from the source, not at contact. Every one of those corrections pushes the true gonadal dose down, and none of them can be pinned without gamma spectroscopy and a geometry model that nobody has published.

So the honest move is to take the contact reading as a ceiling, derate it hard, and see where the conclusion breaks. Eight hours a night, as directed, converting at roughly 0.0093 Gy per roentgen in soft tissue.

The claim holds down to about a fourteenfold derating and fails past that. I want to be exact about that, because my first pass through this said the finding was robust across the whole plausible range, and it is not. Below roughly a fourteenth of the contact reading the device becomes, dosimetrically, a piece of jewellery.

Two things push the other way. Radium 226 has a half life of sixteen centuries, so the specimen measured a hundred years on has barely faded. But Bailey's other famous product, Radithor, contained radium 228 alongside it, and radium 228 has a half life of under six years. If the blotter strips were charged from the same stock, the device sold in 1925 was hotter than the object anyone has measured since, and by a wide margin in its first decade. A century of radon escaping through a case we know leaked cuts the same direction. I flag that as an open question rather than an assumption, because nobody has run a gamma spectrum on one of these and published it.

Here is the detail that closes the file. Look again at the two threshold pairs. Causing permanent sterility takes 3.5 to 6.0 Gy delivered all at once, but only 2.0 Gy per year delivered slowly. Protracted exposure is more efficient at permanent gonadal damage, not less, because a continuous low dose keeps killing stem spermatogonia faster than the surviving ones can repopulate. There is no interval in which the tissue is left alone to recover.

Every night. Indefinitely. Against the gonads. Of all the delivery schedules available, the instruction card specified the worst one.

Not with a reckoning. American Endocrine Laboratories simply stopped manufacturing in 1929 and wound up the following spring. What actually broke the radium consumer market was a different Bailey product and a different customer, the Pittsburgh industrialist Eben Byers, whose death from Radithor in 1932 did the work that no regulator had managed. The Radiendocrinator did not get a scandal. It got obsolescence.

William Bailey never conceded anything. He held that he had drunk more radium water than any man alive and was fine. He died in May 1949, aged 64, of bladder cancer. His body was exhumed roughly two decades later and found to be substantially radioactive.

That last sentence deserves a caveat, because it is the single most repeated fact about Bailey and the sources cannot agree on when it happened. Published accounts variously give 1969, 1970, and the early 1960s, and the specific measured figures that circulate are not traceable to a named report. The exhumation is well enough attested to state. The details around it have been passed hand to hand for so long that they have worn smooth, which is its own small lesson about how confidently we repeat the stories that flatter our hindsight.