Benjamin Franklin published his Gulf Stream chart in 1770 in England, where it was completely ignored. Subsequent versions were printed in France in 1778 and the U.S. in 1786. The British edition of the chart, which was the original, was so thoroughly ignored that everyone assumed it was lost forever until Phil Richardson, a Woods Hole oceanographer and Gulf Stream expert, discovered it in the Bibliothèque Nationale in Paris in 1980.
Source: Wikipedia
A French national hero at age 55, in 1878 Louis Pasteur discreetly told his family never to reveal his laboratory notebooks to anyone. His family obeyed, and all his documents were held and inherited in secrecy. Finally, in 1964 Pasteur's grandson and last surviving male descendant, Pasteur Valley-Radot, donated the papers to the French national library (Bibliothèque nationale). Yet the papers were restricted for historical studies until the death of Valley-Radot in 1971. The documents were given a catalogue number only in 1985.
Source: Wikipedia