The Third Level in the story refers to a mysterious subway that takes passengers to a different time period. The story is set in the 1950s, and the Third Level takes passengers to the 1890s. The story is narrated by Charley, who is a nervous, stressed-out accountant. He is fascinated by the idea of the Third Level and begins to believe that it is real.

How Charley found out he had bumped into the past:

Charley is fascinated by the Third Level and begins to spend more and more time at the subway station, hoping to catch a glimpse of it. One day, while he is waiting for his train, he accidentally bumps into an old man who drops a letter. Charley picks up the letter and realizes that it is addressed to someone in the 1890s. He is shocked and confused, but he realizes that he has somehow bumped into the past.

The Third Level:

The Third Level is a mysterious subway that takes passengers to a different time period. It is located in the Grand Central Station in New York City. The subway is said to be hidden behind a door that only appears at certain times of the day. The Third Level takes passengers to the 1890s, a time period that Charley finds fascinating.

Charley's fascination with the Third Level:

Charley is a stressed-out accountant who is fascinated by the idea of the Third Level. He spends more and more time at the subway station, hoping to catch a glimpse of it. He becomes obsessed with the idea and begins to believe that it is real.

Conclusion:

In conclusion, the Third Level is a mysterious subway that takes passengers to a different time period. Charley becomes fascinated by the idea and begins to believe that it is real. He accidentally bumps into an old man and picks up a letter addressed to someone in the 1890s, which confirms his belief that he has bumped into the past.