What are the major events in Frederick Douglass' life in The Narrative of the Life of Frederick Douglass?

Before his escape from slavery, Frederick Douglass recounts several major turning points in his life.  One of the more famous scenes in the text occurs in Chapter 1 when he witnesses this Aunt Hester being beaten by her seemingly sadistic master:

Before he commenced whipping Aunt Hester, he took her into the kitchen, and stripped her from neck to waist, leaving her neck, shoulders, and back, entirely naked.  He then told her to cross her hands, calling her at the same time a d---d b---h.  After crossing her hands, he tied them with a strong rope, and led her to a stool under a large hook in the joist, put in for the purpose.  He made her get upon the stool and tied her hands to the hook.  She now stood fair for his infernal purpose.

Both because of his youth and the transgression involved in seeing such a sight, Douglass narrates that he "hid [himself] in a closet, and dared not venture out till long after the bloody transaction was over."  This scene sets the stage for the brutality of slavery which will serve as a theme in the text.

In reaction to this brutality--and one of his master's claims that slaves ought not learn to read--Douglass enlists the white schoolchildren of Baltimore to help him learn to read.  His new-found literacy leads him to "The Columbian Orator" and its critique of anti-Catholic prejudice.  Upon reading this text:

Freedom now appeared, to disappear no more forever.  It was heard in every sound, and seen in every thing.  It was ever present to torment me with a sense of my wretched condition.  I saw nothing without seeing it, I heard nothing without hearing it, and felt nothing without feeling it.  It looked from every star, it smiled in every calm, breathed in every wind, and moved in every storm.

As you can see from this quote, Douglass gains an ambition for "Freedom," and an overwhelming desire to be emancipated.  The crucial turning point in his emancipation comes in a physical struggle he has with his master Covey.  Because Covey threatens to beat him for insubordination, Douglass:

resolved to fight; and suiting my action to the resolution, I seized Covey hard by the throat; and as I did so, I rose.  He held on to me, and I to him....  I seized him with both hands by his collar, and brought him by a sudden snatch to the ground....

After this encounter, Douglass' resolve to be free solidifies, and he eventually escapes from slavery, though he does not indicate how.  This newly-won freedom is not without its difficulties, however.  When working at a shipyard in Baltimore, he encounters racism in the white carpenters with whom he is working:

Many of the black carpenters were freemen.  Things seemed to be going on very well.  All at once, the white carpenters knocked off, and said they would not work with free colored workmen.  Their reason for this, as alleged, was, that if free colored carpenters were encouraged, they would soon take the trade into their own hands, and poor white men would be thrown out of employment.

These four events (the beating of Aunt Hester, learning to read, fighting with Covey, and encountering Northern white racism) serve as key turning points in the Narrative, exemplifying many of its major themes such as human rights, slave self-determination, and the importance of literacy.