To Whomever finds this information,
First, I congratulate you for finding my research. I knew eventually it would be found. Hopefully it is long obsolete and destined for museums in rare documents.
I apologize I don't have time to answer all of your questions, but suffice it to say, you have stumbled upon my research into time travel. Yes, it is real and it is possible. In fact, by the time Marty and I destroyed my original machine, it had become almost routine. However, after returning to my time for the last time, I could not bear to destroy my research and schematics on the subject. It is the curse of being a scientist my friends.
Inside the manila envelope you found attached to this letter is the complete schematics for my flux capacitor and all associated wiring required to make time jumps. I warn you though, the precise mathematics of finding the correct speed for time travel requires a doctorate in mathematics or similar. If you do not, I recommend putting this research right back where you found it.
I also have a grave reminder for you. Time travel is dangerous and can have many effects that are often not obvious at first and can be terribly difficult to repair. (see my time logs) Please, I beg of you, please, do not use this to create a time machine for selfish reasons. Only use it if the timeline has been compromised already.
I'm afraid my time has run out. Good bye and God Speed my friend.
Sincerely,
Emmet Brown, PhD…
"Hey Mark," Alex Fontaine yelled from across the building. "Look what I've found!"
Mark came running over and began reading over the documents, his jaw slowly moving towards the floor.