"Back There" Twilight Zone

I have recenly watched a Twilight Zone episode, "Back There". In the episode, a man, Corrigen, is playing cards with some friends of his, discussing time travel and wondering if they could change major events in history. Corrigen leaves the table, and accidently runs into William, a servant. They both apologize to one another and the man leaves the house. Then next thing you know, he has travelled back in time, without a machine. He goes to his home to find that the date was April 14, 1865, the day Lincon died. He tried to warn someone, but he ended up in jail. A man came and took Corrigen with him. The other man told him that he helps with people who are mentally ill. The other man offers a drink to Corrigen, and later Corrigen realizes that his drink had a drug that made Corrigen not able to walk and warn people. The other man gives Corrigen his hanky, and locks him in the room. The hanky has the intials JWB, John Wilkes Booth. Corrigen passes out. A man comes in and finds Corrigen and Corrigen wakes up and the man tells Corrigen that he believes him and that they need more people protecting the president. As soon as they were going to do that, they hear from the street someone screaming about Lincon being shot. It was too late. Corrigen then walks around town and travels back to the present. He runs into another servent and asks where William is. The servent says that he knows no one with the name of William on the servent team. Corrigen goes back to the table with his friends and they ask why he is back so soon. He becomes confused but shakes it off. One of  the men says something about another man with the name of William and Ta Da! there is William with fancy clothes and such. William explains how his great grandfather went around town trying to tell people that Lincon was gonna die. No one where he got the info, but he became very famous in the police world making him very rich. William has inherited his money, and is now rich and not a servent. THE END. This episode shows that people cannot change big events, like Lincon getting shot, but people can change little things, like William. I have noticed that this occurs a lot in time travel. This episode also shows that you do not need a time machine to go back. We mostly think of time travel with a time machine and Corrigen went back in time without a machine and came back perfectly fine. So if we wanted time travel to happen right now, would we need a time machine or just us? Come back ASAP for more fun with time travel!