“…the men who control their manufacture are wise enough to stop at a reasonable position, and not develop unduly a power that could be made dangerous.” [New York Tribune, May 17, 1918, Page 4]
The men in question were from the Worthington Golf Ball Company, who, in 1910 began manufacturing their ‘Radio Golf Balls’. Whether the balls were dangerous or not is open to question, for they had a radioactive core of radium – with approximately 150 Bq (4 nCi). Get more background, if you’d like some, from the Oak Ridge Associated Universities website.
The camera-less radiograph above was produced by a ball directly irradiating photographic paper.