In a message dated 11/22/2009 10:48:52 PM Pacific Standard Time, smolensk@eunet.rs writes:

Digitize them and publish them on the Internet, but insure them, so that if heirs ever appear a reasonable royalty may be paid to them.>>

Heirs do not necessarily get any benefit from copyrighted works of their ancestors. You *may* but only if the work has been re-registered. I think what you mean is, if the work was still properly copyrighted then they would get royalties, but not all works of authors of unknown death date are still under copyright protection. Just some.