Lithium hydride
Before the Castle Bravo nuclear weapons test in 1954, it was thought that only the less common isotope lithium-6 would breed tritium when struck with fast neutrons. The Castle Bravo test showed (accidentally) that the more plentiful lithium-7 also does so under extreme conditions, albeit by an endothermic reaction.
Castle of Castelo Branco
A storm caused a landslide that destroyed the eastern/northern corner tower, leading to a formal request to the DGEMN to begin a project of restoration and lookout. Simultaneously, the municipality solicited ideas for the reconstruction of the castle from Engineer Manuel Tavares dos Santos, but lacking any funds, this project was abandoned. By 1975, the possibility of demolishing the wall along "Rua Vaz Preto" was examined: the DGEMN analyzed the walls along this corridor in 1977, in order to determine the viability, while the municipal authority expropriated homes along the segment of the walls.