DescriptionRadium worker using lead shield 1929.jpg
English: A technician in the early 20th century (probably 1920s) working with
radium using primitive
radiation protection. From 1904 radium was used in medicine to treat cancer, but adequate protection from its rays was slow to develop. The worker is standing behind a lead shield to protect himself from the
gamma rays. He looks through a window of lead glass. His right hand is covered by a lead shield.
This 1929 issue of Popular Science magazine would have the copyright renewed in 1957. Online page scans of the Catalog of Copyright Entries, published by the US Copyright Office can be found
here. Search of the Renewals for Periodicals for 1956, 1957, and 1958 show no renewal entries for Popular Science. Therefore the copyright was not renewed and it is in the public domain.
Licensing
Public domainPublic domainfalsefalse
This work is in the public domain because it was published in the United States between 1929 and 1963, and although there may or may not have been a copyright notice, the copyright was not renewed. For further explanation, see
Commons:Hirtle chart and
the copyright renewal logs. Note that it may still be copyrighted in jurisdictions that do not apply the
rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years
p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.