The Old Notebook is a Mission Item used in the Osiris Campaign Mission Lost Knowledge Part 6. The Mission requires the Prospector to visit the Lost Scientist at Favela on Crescent Falls and collect the Old Notebook item.
See its location on the Interactive Map, as well as on the image below.
Description
An Osiris researcher's notebook. It's seen better days. Full of formulas, drawings, and long paragraphs regarding the unnatural evolution and mutations of Fortuna III's fauna caused by Progenitor terraformers.
Story
In Lost Knowledge, Osiris is investigating the mysteries of Fortuna III. As part of this, they had a group of scientists at the Extinct Creatures Lab on Crescent Falls. The ship carrying the head of operations at the lab, Dr. Farinha, and his equipment, crashed in the Jungle on Bright Sands. After collecting the Flight Recorder, the Prospector has to visit Favela, as it is thought that Dr. Farinha survived the crash and took shelter there. Dr. Farinha's remains are found inside one of the buildings, and next to his body lies the Old Notebook. The Old Notebook has research about the Crystal Cave written in it. It states that the Crystal Caverns were made of a material similar to materials made by the Progenitors. The crystals are more resistant than any other material Osiris thought imaginable. With the help of the research, Osiris develops the Orbital Cannon.